Thank you for the clarification. Anyway, what do you mean by "Average range"? Or "sets"?
Supposed to be "stats".
I typo'd and didn't correct that until now -_-
Anyway, average range being "what's the usual ATK and DEF for monsters of equivalent Level/Rank/Link Rating (but don't have any negative drawbacks for the most part)". For example, Level 4 monsters usually can hit 1900 ATK without being subjected to summoning restrictions or negative effects (and/or being made into Vanillas). DEF, you can usually go up to around 2200/2300 before negative effects kick in.
Negative effects being "opponent gains LP, can draw a card, monster is restricted in its summoning and must be summoned by a certain method, blows self up if a certain card isn't on the field too, etc."
Level 8s usually cap at around 3000 before restrictions kick in, though stuff like Super Conductor has 3300 ATK and not any notable restrictions. Ultimate Conductor is a SS-only monster, but has 3500/3200 stats and not very hard to summon comparatively.
Granted, these limits are subject to change based on the gamestate and also depend on the effects you give them. Extra Deck / Special Summon-only monsters usually can go slightly higher given the added work needed to get them out material-wise and whatnot.
For Links, a rule of thumb that gets used nowadays is that a Link Rating is twice that of a standard monster Level, and the corresponding ATK of a Link Monster can be chosen from that.
Like with everything else, there are exceptions to that rule and monsters may have higher stats than average if the investment required is higher. Konami may not add them on their own, but it does not mean you cannot try to find something that'll work out.