My thought is we need to be patient, let see what things look like with, 500 active contributors, with 1000, with 10,000. I don't think Wikipedia has actually reached its takeoff point yet.
Experts will come, retired folks, occassional passersby, students. Frankly, I don't want to see any expert (in some field) playing any important role unless they are also expert in the give and take of wikipedia article writing and editing.
It is in that give and take that peer review happens.
If you quit now or greatly modify the system you'll never know how what we do now would have developed.
Fred