Redbay 950-E and a big diesel lump. Self draining decks and could take a wee spray canopy. Double (ish) berths and a heads in there, potentially. As you know, I've done a few miles on these hulls and I like 'em. Tubes are out of the water so economy/speed is reasonable but the hull is very forgiving in the rough.
Obviously I'm biased
As for the big cabin things like the Botnia - very nice and all if you can afford to haul your house around the Irish Sea. Personally, I'd just spend the difference on nice hotel rooms and luxury restaurants - there are plenty of both in those cruising grounds!