Melee guys are very bad - the animation is extremely slow and is not cancellable - you'll get hit by the time you can move again. Foam guy has to be locked into the direction, which makes him SLIGHTLY better than the melee ones.
Every single character has a problem - you have a long cooldown skill that is actually viable at killing enemies, and the primary attack being a direct ticket to game over. It doesn't feel like a twinstick action game, even though it seems to want to be one. The one that gets damaged by his own whirlwind is probably the worst due to the penalty his skill has. Again, whirlwind was pretty much his only viable skill.
Gamepad broke a lot of stuff, which is not very acceptable since twinstick game requires, well, sticks. Though kb seems to not fare any better.
Needs a lot of stuff, both in the controls and balancing department.