Smaller is better, to a point
I agree that smaller is better, up to a point. My first true live aboard was a 28. That was a very dramatic change from a house. Took a while to get used to it, and never did get over the feeling of being a little cramped. There just isn't much room on any boat under 30 feet. Also, pay attention to the beam, and the layout. One of the roomiest boats I have been on, in this size range is an Almand 31. The designer has a bunch to do with interior space.
Dream like you will live forever. Live like you will die tomorrow. ( James Dean )