In all honesty he isn't nearly as bad as half the cards on the banned list.
1.) He can't OHKO I know that seems trivial but he can't. He can do 12 damage but he won't simply KO you.
2.) He is predictable without his ability he really sucks so he has to be played second which means you can force match ups you want to a certain extent.
3.) His bonus doesn't help him win the round in a direct way.
Now I'm not saying that he isn't a strong card far from it. All I know is I'd prefer to play against him than Rolph.