Greetings. Superheavy main here, directed to this thread by a friend, and honestly rather ashamed with how many good cards you missed (read: over half the damn archetype). There are a lot of things wrong with your takes on these cards and the numbers you should run, as well as a few nifty cards you failed to mention. I'm here to tell you about those.
CARDS YOU MENTIONED
Superheavy Samurai Battleball: Okay, first of all, you failed to neglect Levels 9 and 10, the latter of which being perhaps the best Superheavy synchro. Secondly, Superheavies don't have any Level 3 or 4 synchros, nor will we probably get any since those are levels that we basically can't get unless we pull some serious shenanigans. Why does the latter point matter? Because Battleball can only summon Superheavy Samurai synchros with its effect. Definitely run at least two copies, but make sure you're not loading your extra deck with crap you can't even use.
Superheavy Samurai Big Benkei: I'll level with you here, Benkei is my favorite card in the archetype and a big part of why I picked up Superheavies to begin with. Good DEF, makes Susanowo, lets your other main deck Superheavies attack with their DEF, etc. However, after some testing around, he's not so amazingly awesome that you should still run him at 3. Run him at 1 instead and use Jade as your other two copies. The biggest consistency problem you'll probably face when you run three Benkeis is drawing a Benkei when you can't put him on the field. Trust me; it's happened to me many times. On another note, what the fuck does "the bane of the deck" mean in this context? The bane of something is something that it can't stand dealing with. For instance, the bane of Shaddolls is Macro Cosmos or D-Fissure, the bane of HERO is Domain of the True Monarchs, and the bane of Superheavy Samurai is...not Benkei.
Superheavy Samurai Flutist: So first off, Flutist's tribute effect Special Summons any Superheavy; not "uses it as the tributes for their summon". This is an important distinction for two reasons. For one, if your opponent has a floodgate up like Emptiness or Winda, you'll have a hard time using Flutist's summon effect. Secondly, he can tribute himself to summon a Level 4 or lower Superheavy as well. Imagine your opening hand being Scales, Flutist, Trumpeter, and either Coral or Soulhorns. You can Normal Summon Flutist, use its effect to summon Scales, which retrieves your Flutist from the graveyard, then summon Trumpeter with its own effect then make Kyubi, which proceeds to wreck face with Coral/Soulhorns. Shit, if you assume Soulhorns in that scenario you could even make Susanowo by equipping something with it then summoning it with its own effect.
Superheavy Samurai Scales: Minus "Run 3" basically everything you've said here is wrong. Scales gets its effect whether it's Normal or Special Summoned (see the above scenario with Flutist), and only summons one monster from the Graveyard; it would be busted if it summoned two. It definitely makes for good synchro plays, but typically doesn't do much on your first turn due to your lack of a Graveyard. It may also be worth noting that Scales can only summon Level 4 or lower monsters.
Superheavy Samurai General Jade: Or as I like to call it, "Benkeis 2 & 3". The pendulum effect is nice on paper, but 95% of the time you'll want it because it's a Benkei you can summon for only one tribute. This means that Jade and Trumpeter in your hand is an instant Susanowo. Being a pendulum, of course, Jade lacks the advantage of being re-summonable by Drums, which I'll discuss later. Run 2 copies, yes, but don't expect to use it for its pendulum effect.
Superheavy Samurai Coral: As with Scales, nearly everything you've said is wrong. Coral can be a main OTK factor, but in my opinion Soulhorns is far better. Its pendulum effect does say "Once per turn" - right near the beginning and everything - and the draw effect is extremely not worth it unless you're tributing Soulpiercers or Gigagloves. Run 1, tops.
Superheavy Samurai Blue Brawler: Not gonna lie, this card is pretty neat. Unfortunately, depending on how you go about building your Superheavy deck, there's no place for Brawler. He's too much of a standalone card and doesn't really synergize with anything else besides Benkei, so pretty much all of his value comes as a wall that you sit behind until your opponent drops some form of removal. If you're going all-out on the defense, run him sure, but otherwise, I wouldn't bother.
Superheavy Samurai Beast Kyubi: Don't forget that Kyubi only gains DEF based on your opponent's Special Summoned monsters. His base DEF of 2500 is laughable. Honestly, you should only run one of these, and not go for it if you can go for a better synchro (read: literally any other Superheavy synchro). Granted, he does give us a way to deal with annoying Level 7s via Battleball.
Cyber Dragon Nova/Infinity: Highlander already covered this.
Black Rose Dragon: You can't be serious. Superheavies can barely even make 7s, and almost 100% of the time it's because you Special Summoned Trumpeter with its effect, which will effectively lock you out of usuing Black Rose. The only Level 7 that even sometimes works in Superheavies is Superheavy Samurai Ninja Shinobiashi. Don't run at all.
Felgrand & Cipher: Just because Superheavies can make something, it doesn't mean they should. In Cipher's case specifically, it actually removes a lot of OTK ability, since it locks you out of attacking directly for the rest of the turn. You can run a single Felgrand if you find yourself consistently in a position to make it (I've been in such a scenario all of one time, and I've mained this deck for most of the time since it first came out), but don't bother with Cipher.
CARDS YOU DIDN'T MENTION
Trishula, Dragon of the Ice Barrier: Getting this one out of the way first, since it's the only non-SHS card I'll be adding to the list. Completely disregarding what I said just above, Trishula is one of those cards where if you can make it semi-consistently, you stick it in your extra deck. In my experience, this is the only non-SHS synchro you'll be able to make on an almost regular basis, and it's a nice piece of removal (not to mention it's just cool to summon Trishula).
Superheavy Samurai Thief: Setting aside that it being Level 10 is really funny for some reason, Thief is a very powerful card and a necessary one in Superheavies. It's your slower MST equivalent that lets you set the destroyed card to your side of the field. It's also the only method Superheavies have of dealing with Skill Drain, which is by far the card that counters them hardest. Run three, no questions asked.
Superheavy Samurai Transporter: While I personally am not a big fan of Transporter, it has its uses every once in a while, mainly through Battleball plays that also give you a bit of draw power. Run one or two and experiment with synchros and the effect; it might come in handy.
Superheavy Samurai Big Waraji: Like Transporter, I'm not too big on this card, but with Shinobiashi now existing, the maindeck Level 5s might get a bit more useful. Being able to treat this card as two tributes for the Tribute Summon of a Machine-Type monster (any Machine-Type monster, I may add) is nice and all, but in Superheavies specifically, it won't do much if you're only running one Benkei. Same advice as with Transporter for running this card.
Superheavy Samurai Soulpiercer: This is the first of five cards where your failure to mention it tells me you either have never even touched a Superheavy Samurai deck, or that the ones you have touched are really, really bad and/or dated (the latter is quite unlikely, seeing as you mentioned the pendulums). Being able to give a Superheavy Samurai piercing is nice, but the real selling point here is the search effect. Because Superheavies are a synchro-heavy deck and have a couple effects that tribute your monsters, you'll see Soulpiercer hitting the graveyard a LOT if you use it right. It gets its search off being destroyed as an equip, tributed for a card effect, or even just used as a synchro material. Run three, and I'll punch you if I find out you're trying to get away with any less.
Superheavy Samurai Magnet: I've since dropped Brawler in favor of this card. The effect doesn't look like too much at first glance, but Magnet can make some pretty good synchro plays, especially if you summon Scales with the effect. Run at least two.
Superheavy Samurai Soulshield Wall: I personally don't use this anymore, but it's pretty cool regardless. It gives an equipped monster a nice chunk of DEF and can negate an attack targeting it, for those rare instances where something manages to beat over your Superheavy bosses. Since I don't use it anymore, I can't tell you how many (if any at all) to run.
Superheavy Samurai Prepped Defense: This card can and will stop OTKs dead in their tracks. Being Level 3 also means you can make Musashi with it. It's essentially a better Brawler in that regard, with the tradeoff being that you'll have to take some damage first, and that it won't stay invincible forever. Feel free to experiment with this one, though I've come to like it at two.
Superheavy Samurai Gigagloves: The second card where your failure to mention it tells me you don't know much about this archetype. Gigagloves is a key card due to a combination of its level, the ability to re-arrange the top five cards of your deck, and its graveyard effect that can lead into plays where you deal as much as 7600 damage in a single attack. For such a defensive card, Gigagloves is a central part of your offense. Run two at the absolute bare minimum.
Superheavy Samurai Soulfire Suit: The third critical card you failed to mention. The entire point of Superheavy Samurai is to play a strong defense, and few cards embody that goal better than Soulfire. Its equip effect is all fine and dandy since it can turn any Superheavy Samurai monster into a Level 5 monster (depending on how you build the deck, this could allow for those Cyber Dragon plays), permitting you to make synchros you normally would struggle to. However, the fun stuff comes from its hand trap effect. Rendering a single monster immune to destruction for a turn is about as Superheavy Samurai-esque as it gets. If you're not running this at three, you're doing it wrong.
Superheavy Samurai Trumpeter: Before Battleball, there was Trumpeter. Being a tuner that Special Summons itself from the hand for free is really nice. Being a tuner that Special Summons itself from the Graveyard if you tributed it for a Tribute Summon is even better. As I mentioned with Jade, this plus the aforementioned pendulum make an instant Susanowo off only two cards. Plus, as far as Superheavy Samurai go, this thing's adorable. He's just like "I'll stand here and doot at the enemy! Don't worry guys I've got this!" Run at three.
Superheavy Samurai Drum: This card is very fun; more fun than it probably should be. Being a Level 1 tuner as opposed to Trumpeter and Battleball being Level 2 means running Drums gives you more synchro options, and to sweeten the deal, it Special Summons a Superheavy Samurai from the Graveyard if it's destroyed. Sadly, this deck doesn't have many ways to destroy its own monsters (it would kind of defeat the point and flavor of the deck), but Drum should definitely be run at at least two in your deck.
Superheavy Samurai Soulbuster Gauntlet: The fourth entry in "Why did you not bring this card up?", Soulbuster is the deck's themed Honest. It doubles the DEF of a Superheavy that battles a monster until the end of the turn. Let me re-iterate that. Until the end of the turn. The DEF boost sticks even after that battle, meaning if you are using Soulhorns/Coral in tandem with this, you'll do tons of damage. This is also part of the aforementioned setups with Gigagloves; pimp-slapping an opposing boss for 7600 damage is so satisfying. Run at three, or I'll pimp-slap you for 7600 damage.
Superheavy Samurai Soulhorns: In my opinion, a better Coral. Soulhorns - unlike its pendulum counterpart - is not a pendulum monster. That doesn't sound very stunning at first, but this means it goes to the Graveyard when destroyed. Which in turn means you can summon it back with Scales or Drum. In addition, Soulhorn allows a second attack no matter what; you can attack directly twice with Susanowo and nearly win the game should such a scenario come up. Soulhorns is also capable of Special Summoning itself while equipped to a monster; a trait in Superheavies that it shares only with Soulclaw, who I did not put in this list. Run at least two copies of Soulhorn, and add a third or remove the second as necessary.
Superheavy Samurai Soularbitrator: The fifth and final card that tells me you don't know as much about this archetype as you may think you do. It's a searcher. That's most of the appeal; Superheavies kind of need those. However, the real fun comes from how you can tribute Gigagloves or Soulpiercer (or a Gigagloves equipped with a Soulpiercer!) with Arbitrator's effect, which causes you to also gain the respective effects of those monsters as well. It also forces your opponent to only attack the equipped monster, but you probably won't get much out of that. Run at three, and remove the third only if you're in dire need of deck space.
Superheavy Samurai Ninja Sarutobi: The Level 8 synchro, which is another MST that also deals burn damage. Unlike Thief and Shutendoji, Sarutobi can also hit your own backrow. This probably doesn't sound very appealing, and honestly it isn't most of the time. However, this means Sarutobi can pop a Soulpiercer you equip it with, netting you 500 damage to your opponent and a search to the hand. That said, you probably won't make Sarutobi too often. Run at one or two.
Superheavy Samurai Ninja Shinobiashi: I can't really blame you for leaving this one out; it's pretty new. Shinobiashi is the Level 7 synchro in the archetype, and acts as a pseudo-Drill Warrior and Bram mixed into one bundle. Something interesting to note about Shinobiashi is that his effect only halves his original DEF; if you equipped it with, say, Soulshield wall, he'll keep the entire 1200-DEF boost from that, giving you a 2600-DEF direct attacker. Additionally, Trumpeter plus any Level 3 Superheavy makes for an instant Shinobiashi by synchroing into Musashi, using Musashi's effect to get Trumpeter back, then synching Musashi & Trumpeter together for Shinobiashi. Run at one or two.
Superheavy Samurai Swordmaster Musashi: The fact is that Musashi can make some very interesting plays. As the Level 5 synchro, making Musashi can be a bit awkward, but he'll reward you for it by returning any Machine-Type monster in your Graveyard back to your hand. Any Machine-Type monster. Musashi can actually be splashed into other decks, and in this deck, should be run at two. If you find yourself constantly summoning Musashis, you could probably get away with a third, but I don't suggest it.
Hand Trap Monsters: Maxx C, Veiler, and so on. Because Superheavies don't like using Spells/Traps, hand trap monsters can really benefit them. Maxx C in particular should be helpful, but I'm weird and choose not to run it. Should you use Maxx C, I'd suggest at least two copies. Can't speak for other monsters.
Self-banishing S/Ts & Bait Doll: Think of cards like Galaxy Cyclone or Breakthrough Skill. They have a distinct quality where they banish themselves from the Graveyard, so that they no longer interfere with the effects of your Superheavy Samurai monsters. I personally don't like using them since it defeats the point of playing Superheavies, but you're free to do what you want. Even if you're a non-steadfast bastard for using them. Bait Doll deserves a special mention here too, since it doesn't go to the Graveyard unless it's negated. This makes it handy recurring removal, but you'll be in high water if somebody negates your Bait Doll. I'd advise heavily against Bait Doll, but again, do what you want.
Whew, that was a lot of typing! Hopefully this long-ass post helped you out. Like I said somewhere in here, I've been maining Superheavy Samurai for a while, so I tend to know what I'm doing with the deck. If you have any questions, just let me know (>w<)/