probably not unless they get way ahead of schedule
making the hammer 10% slower will help alot. i think its not true, sadly. i can predict enemy movements and time it better, soo either it gets slower and people do worse, or it can be worse to swing faster. or it can be the exact opposite
my idea of classes make certain things look op, but it isn't. its all sort of balanced when you think of it. something easily counters this class, like a ninja being to fast for the knight, but berserkers bring him down fast with stun and execution. or just timing his throwing axe right. and the knight counters a berserker easy, having a shield to block axes and throwing axes, and spin attacking him.
and then adding some enemies based off alll the classes is a unique challange