Out of BHD I would expect 90-100 hour months in the summer, in excess of 800 hrs per year total assuming full time, likely close to 900 in reality.
Flight/duty hours are relatively on par, in essence, when at work you will be flying. Nightstops will vary depending on the crewing levels at other bases, basically you will only night-stop out of BHD to cover other bases, until you are LCY trained, (not everyone gets trained) Belfast generally has the lowest level of night stops within the company.
Expect to be bottom of seniority for holidays so will depend on demand obviously when you are looking to book.
If base is your priority, then Flybe might be a good option for you. BHD is the most stable and best one in the company (that is common opinion in case anyone claims bias!), it has the best crews to go on a day out with, airport access and closing times limit disruption compared to other bases, and lastly BHD will never be closed as long as Flybe exists as it is one of the company's main breadwinners for the dash.
Stability? Well who knows, but they are profitable and generally the routes are busy (except Saads obsession with BHD-LPL but thats another story).
Cons: 6 sector days are the worst, and you will do plenty of them out of BHD