First effect: It's okay. I think 1000 would be enough though. Second effect: A neat Catastor-eske effect to make use of Link Zones. Though the following effect seems rather unnecessary and excessive. It's already capable of being a beatstick and destruction. I think benefiting from said destruction is unneeded. Maybe you could argue the Summoning requirements justify this, but even then, I think you could bring it down to 3 effect monsters witht the same Level/Rank.
Also, our wording's off. I think it'd be:
If all cards Linked to this card have the same Level/Rank (min 2) this card gains 1500 ATK. At the start of the Damage Step, if a card linked to this card battles: You can discard 1 card; destroy your opponent's card. Once per turn, if an opponent's card is destroyed during the Battle Phase: Add to your hand one Level 1 monster in your Graveyard, then reveal your entire hand; if all the revealed monsters (min 2) Levels are 1: Draw 1 card.
Target 1 monster you control and 1 monster in your Graveyard or either player's side of the field: The name and Level of the monster you control becomes the same as the monster in the Graveyard. These changes last until the End Phase.
Wait. That only states "in the Graveyard" for the name and Level.
Wouldn't it be more:
Target 1 monster you control and 1 monster in your Graveyard or either player's side of the field: The name and Level of the first target become the same as the second target's. These changes last until the End Phase.
Target 1 monster you control and 1 monster on the field or in your Graveyard; until the End Phase, the name, Level, Attribute, and Type of the first target becomes the name, Level, Attribute, and Type of the second target.
Perhaps the Link Marker effect could be used for you to benefit off your opponent's Link monster (at least I think so). That or you could just place it on a Zone they can't access yet. Otherwise it's just a slightly better yet conditional Fiendish Chain. Perhaps you could give it a small self-banish effect to activate in the Graveyard; maybe something to slightly hinder Link monsters?