We just went through this, again. If you truly do not want to not purchase again for awhile, then put size aside for a moment, think real hard about the loft concept - great while they are small, not so good as the age, sizewise, and defently not an advantage when the 10/11 year old wants to begin bringing friends. We started w/ a pop up and as the kids grew we upgraded to a 33 bunkhouse (4 bunks in back - Puma BHSS), we just traded it off on a Sirerra 365SAQ - 5th wheel and second bath. FYI our kids are 11, 9, and 5 so as you can figure we did all this in about a 5yr timeframe. Hopefully this one will last us awhile, besides the slides in back bunkhouse to create more space and a second bath, the space for the entertainment system back there - we allow early morning and rain day use, the additional pull out bed (5th) in the back helped the we want to bring friends issue without having to drop the table or setup the air bed. Seperate from all that the "boss" liked the concept of outside frig, for kids snacks and soda/water and the outside direct access to the back bath, no tracking dirt through the TT to get to the bathroom. Back to size, we camp all over including national forest areas while they are tight I have not had any real issues with getting our 35 into and out small sports it just takes time and pratice.
Bottom line - if you want to keep camping as the kids hit the teens size it in now.
my 2 cents......