There is an interesting post on SLUinverse about Avatar 2.0 by Darien Caldwell. See: A Modest Proposal: Moving toward Avatar 2.0.
Darien’s idea of making a new avatar compatible with the current avatar’s UVMaps is a deal breaker for me. That just drags those problems along. Fixing the UVMaps and attempting to use older clothing made for the previous UVMap is going to be a problem causing even more distortion.
Darien does key in on the layering problem. We can layer system clothes. We cannot layer textures on objects, like mesh avatar bodies. Adding that capability would likely be a complex change to the system. Whether it is or not, it would allow the use of even more textures. With the texture load increase coming from Materials use, that could be a serious lag producer.