Personally, I would go with a Wilderness Systems Pungo if I were looking for a sit in type. You have to think about getting in and out of that thing when you're wearing your "thick" shirt.
Seriously though. The Pungo is one of the better sit in types suited for all of the above and they have a larger cockpit opening to allow easier entry and exit. I don't know about you, but if my legs start getting cramped and I can't move them, I start getting anxious to get out.
Something to think about.