I can't comment on points 2,3,4 since I've yet to see these aspects of the game, but classes shouldn't be balanced. They should all excel in different things and be weak in other ways.
Maybe some balancing is in order so not everyone will end up playing the same class, but overall rogues, rangers and bards shouldn't probably be doing aoe farming effectively. Similarly if Warriors have good survivability and damage, maybe it should come at a cost of mobility.
ALPHA