FRA has been doing the rounds for some time. It was operated daily a few years ago by one of BM's Fokker 70s, it did ok from what I can remember, but being only once daily in the middle of the afternoon, it was never going to take critical yield away from the competing services at BHX. There has been a lot of talk at baby at EMA, that regional will be introducing a second Embraer into EMA, possibly to launch a new German route or some of the North Sea destinations we fly from other airports, but until I see a second a/c, also considering slot constraints at FRA, I'm not sure.
I heard from a colleague of mine at Tiny Town that bmibaby at EMA is definitely getting no additional based units next summer, though apparently the bmi charter programme might be larger.