Many Euro airlines are now using the 145 for short hops (40 mins or thereabouts), and find it economical. It isn't a ground gripper if you don't fill it up with gas - in any case, hard to see many airports that it would be likely to serve, where runway length is a problem.
Not sure why you think the 328 is les economical than the SAAB 2000 - it most definitely is not. Ask Crossair/Islandflug.
I see you completely failed to mention the Q400, which in terms of operating specifics, beats the old-school Q300/ATR/340 hands down. It has lower pax-per-seat-mile specifics than the 737.