Two other cities quickly come to mind for new nonstop service -- LIT and BHM. In addition, the CRJ-700 and the EMB-170/175 both have significantly greater range than the current crop of 50-seaters, so there might even be nonstop service from DEN to places like ORF, BUF and PVD, among others. Similar opportunities undoubtedly exist at United''s other hubs for SkyWest and the other United Express carriers to operate longer-haul flights (SFO-OMA, ORD-EUG and IAD-COS, for example).
Also, with United''s move to reject its agreement with Great Lakes, I suspect that SkyWest will move some of its Brasilias into the DEN hub (to serve some fairly small cities like Cheyenne and Scottsbluff) as more of its West Coast flights are operated with RJs.