I don't know Dunblane, and my only trips near Paisley have been to the airport and back, but from everything I've read about Paisley, it sounds like it's a large town that is somewhat depressed and is trying to gentrify itself into something more, but facing pushback from the working locals. These are things that I mostly heard about on Reddit, but a lot of them are from residents.
I'm not sure what you're looking for in a B and B; but I doubt if you'll find anything that luxurious in Paisley. It might help if you'd add your question in your title. For example, edit it and have it read something like "Would like recommendations for an excellent B&B or hotel in Glasgow." That way you might get more responses from others who have stayed in more luxurious places.
Also, you might try checking Booking.com, which has a number of really nice places, and you can check the recommendations, which are verified recs from those who have stayed there. If you get anything rated at 8+ or above, it's going to be pretty good.