As mentioned the chassis length limit is a show stopper. If you move up into a 36' coach there are several available from different builders. In general you're going to need something with an Cummins ISC engine coupled with an Allison 3000 series transmission to get the towing capacity needed. You'll also need to do a bit of math home work to insure any coach you have your eye on has the available capacity to meet your towing needs.
If you go back eight years or so the shine of the opulent does wear off some and the coach price might fit your budget. I've always liked the Tiffin Phaeton line and a 2008 or so 36QSH might fit your wants and needs. The other major builds should have something very similar on the same chassis.