I would have to disagree with your statement, Here is a small list of the most common blocks used for building, Using mostly sloped blocks helps you lower your triangle count instead of using just cubes
A level playing field is all we really need to keep things fair for both care bears and PVPers.
While the idea of multi level classes for factions sounds good its also seems very exploitable, ex a current 10 man faction could break up in to 10 separate factions then ally together now you are stuck being camped by 10 class 5 at once.
I dont have a good answer for what an ideal class size should be with the changes that 5.1 but as it seems now the smaller the class the less lag there is