When one considers the Hall of the Worlds and even the diferent races that drop in at Honest John's place, Ray has the vehicle to introduce more races; millions of planets to draw from, and the possibilities are endless. For that matter, he could even come up with a 'lost' race that's been living say, beyond the Teeth of the World on Midkemia.
On the surface it sounds like it would be fun and interesting, but I've always operated on the 'KISS' principle, and plots could get overentangled very quickly. As we have discussed, it's hard enough sometimes just to keep track of characters chronologically as is!
Two of the things that make Ray a better writer than many others, IMO, is one, the fact that his characters follow a chronological line. Years pass, people die, others replace them, etc. The other is that he doesn't get so hopelessly entangled in a plot that he can't find a satisfactory stopping place - resolve at least some of the conflict or whatever -before moving on to the next book.
The reason I stopped reading WOT (except in used paperback) about 5 yrs ago is because RJ seems to be writing just for the money, hauling out more and more characters, different races, etc, w/o giving the reader any resolution.
In one way the idea of introducing new races is appealing, but I'd hate to see Ray doing it just to throw words on paper. So far even with th longevity of the series, he hasn't caught 'Robert Jordan disease', as some fant fans are now calling it.
So... I really don't know... comments, anyone?