How to know a Champion is Good
So maybe some people still ask this question.
Its simple.
Its a good champ if its can take not only advantage class but a lot of other classes even its disadvantage class because of its big damage or damage type or immunities or easy to play or the combination of those things.
Ex.
Kate Bishop can take Mutants because not rely on bleed but coldsnap
Red Magneto can take Tech because its good against metal, boost the specials
Future Ant-Man can take Cosmic because its potent power drain, damage cap, disintegration, also the resistance
Cosmic Ghost Rider can take Mystic because its damage is so big and quick, also the immunities
Kushala can take Science because the various type of damage like soulbarb, also the immunities
Photon can take Skill because its energy damage and immune to bleed
So, if its a "counter alot" type champ, not only a "counter someone" type champ then its a sign of a good champ or even top tier.
In general, that is my method, but maybe there are other method that we can use.