I agree that Loganair were the big hope. I suspect they might be back. I doubt Eastern/Flybe will try Belfast as it'll eat into their NCL-BHD service. Personally I reckon MME's aforementioned catchment area could surely sustain a weekend service to DUB on Ryanair.
Think I've said it before on here, but the demographic that used Globespan, BMIBaby, and a service to the Dominican Republic when NCL didn't have one, hasn't gone anywhere.
Just thinking aloud here...