If they operated the 737-700 or the Airbus 319, I wouldnt be surprised if they chose to operate the seat configuration the same as the American no-frills airlines who tend to offer a bit more seat pitch, especially as flybe do advertise that they have the best seat pitch of any no-frills airline. Perhaps a -700 in a 138-seat configuation like Southwest, or a 132-seat 319 like Fronteir.
I'm looking forward to seeing the outcome of it all. I'm surprised that they havent looked at Bombardier's new C-series of 100 - 150 seat jets.