I'd rather have more 50 seaters vs. 76 seaters. Taken to the extreme, would you rather have 400 34 seat SAABs or 100 76 seat EMB175's? I would bet most would choose the SAABs.
It would be difficult to staff more 50 seaters vs. less 76 seaters, plus with a cap on anything above 50 seats at mainline, you'd probably see more and more 100 seaters there.
The 50 seater is a great airplane to bring in people from outstations, but what you see the 175's doing is mainline type flying. Personally I want to get away from the regionals doing mainline type flying and more 30 min-1 hour long legs from smaller outstations like Erie, Roanoke, Melbourne, etc.