Recommend going to your local trailer dealers and look around at various sizes and configurations. We did this 7 yrs ago looking to buy a used TT, had an idea of what we “wanted” (bunkhouse) but actually went with a Fleetwood Wilderness 26rls.
Our layout is similar to yours (wilderness 26rls) same issue, i just deal with it. I hook up the hoses so all i need to do is get under and pull the handle, or if not in a park with full hookups I just let the honey wagon come by and they take car...
X3 on the Viair, I use the 400P http://www.viaircorp.com/400P.html works great airing up my jeep tires 35s and sure they wiuld do fine with rv/truck tires.
TV: 2005 Silverado 2500HD Crew cab 4x4 6.6 diesel 12k tow capacitytrailer: 2009 Fleetwood Wilderness 260RLS 7900 GVWRweight dist. hitch and air spring kit make for easy towing.
Looks like you won't have a lot of wiggle room and you definitely won't get very good mileage towing. Like the previous poster, the average MPG I get towing is appx 12, but that is a 2500HD silverado with 6.6 duramax towing 7500lbs. If you go with...