What are you people talking about!? Brainz is far from broken.
The only thing that needs addressing is the arc damage from electro and maybe a buff for party brainz. Everything else is fine. I know he is a melee class, but he is too slow to be 100% reliant on getting near a plant in which most of them can outright cancel or nullify him thus he has a beam. A chomper has two clean options to beat not only his twister but his attacks. Even a low level base cactus can win a sniping match against electro brainz.
Electro's beam is only strong against a group. 1vs1 and he will burn out before he can finish a base cactus. Even Pops Corn can beat any beam 1vs1 at sniping range, without his damage upgrade. The twister you all fear so much is one of the easiest abilities to counter in the game.