I've read about 738s not being the most ideal aircraft for BRS before rog, although being a layman in this field I have no idea of the detailed technical reasons, albeit you have given a summary.
TUI has had 738s based at BRS alongside the 757s for the past few years. I have no idea what if any operational constraints have been thrown up. Ryanair also operates the type from BRS of course and has done so for many years.
On another subject the AAIB report has been published on the incident in December 2017 when a bmi regional (as it was then called) E145 left the runway after landing.
https://assets.publishing.service.go...CKAG_01-19.pdf
The report concludes that the accident arose "as a result of the inadvertent selection of the Emergency/Parking brake instead of the speed brake".