Making any kind of major architectural changes to the PerlMonks infrastructure is virtually impossible.
A better approach, imho, to making "a better PerlMonks" is to start with a framework you like and customize it with the user-level features of PerlMonks which have enabled it to support a community so effectively — i.e. moderation, XP, sections, real-time chat, etc.
Then, of course, you'll need gods with the right balance of priorities to keep things free but orderly. That will be the hardest part.