I was holding out too...I'm prepared to winterize as soon as my forecast calls for it. Some years...I get a trip or two in Nov/Dec.
Regarding ever feeling cramped. It's all about perspective and use. My family of 4 (big people) feels like we are in a castle...of course, we came from a 15'TT. Our habits are that we are almost always outside, unless the weather demands us inside. When it does, we suck it up. I think the discomfort with being inside has more to do with entertainment options than it does with space.
All that said, I believe we handle issue like this better than most families.