I can't get a gooseneck, as there is a possible motorhome purchase in the future. If I pay premium price to have a trailer built to my specs, I plan on keeping it around a while.
I know changing tires is the easy solution, but I REALLY don't want to have to change tires. Can you imagine getting back from a long, hard day on the trail, (with possible rain, snow, wind, cold) and having to get out a jack and swap tires every time before I can put it in the trailer? Not to mention trying to jack on the parking lots that are usually sand, gravel, or not level. It wouldn't be the end of the world, but it would suck. If my rig were road legal and I could get from campground / motel to trailhead, it wouldn't be so bad.
Lots of thinking, researching, measuring, and drawing to do yet.
Thanks for the advice Steve and everybody, its much appreciated.