Here is my long list.
Vile Bile: ugly, most hated!
Kraken lord: plain shit
Dust devil: even shittier
Banshee: whats the point?
Centaur of attention: useless at high team lvl
Shadow Assassin: same as centaur
Faith healer: this guy heals after your team is ripped
Snap dragon: no matter what runes to put, dies fast
Zombie squire: shittiest hero of all time
I have played with all heroes, except burned one, vulture and void. I think they are good tho
Btw some of heros are only usefull with legendary. Or with right runes or at high levels.
But the ones that i listed barely become useful except Vile bile. I listed her because she is ugly hehe