I have Marathon tires on my TT. They were put on in 2014. They have been from Texas to Tennessee and back, to Niagara Falls, to New Brunswick and back, then to Colorado, Utah and back. So far so good.
We have a travel trailer for sale that would probably fit your needs. It is a 2013 Cherokee Grey Wolf 26BH. Our son pulls it with a 2010 Expedition to a family reunion once a year. It comes with a power awning, electric tongue jack, WDH, spare tire, ...
There are rear living plans where you do not have to go through the bath to get to the bed room. The passage is to the side. The Wildwood 27rlss is one, although there are others.