the game was never unbalanced! sure there are some clear top tier characters like phoenix, dante, wesker, wolverine, the dog, magneto. but it is not like they are so far ahead the mid tier characters cant beat them, everyone has some good moves they can abuse, whether is assist or point, especially damage wise a lot of characters outside of the top tiers can pretty much touch of death people with the right assist.
my team is hulk, magneto, ironman, hardly top tier material. but i still beat some tier huggers because if hulk hits you, you are dead
most ocukers dont like it because they cant reactor fast enough to a combo, or mash out random dps and ultras, and the game is too technical in terms of how to defend yourself against cheap moves and team building.