I understand your thinking and I'm only 4 years younger than you. I go back and forth all the time with what I really want in an RV and how I like to travel. I'd get a nice Sportsmobile 4x4 if I could rationalize buying one. Having had a decent TC, and as much as I liked it, I like a Class B van even better but I'd still want a home base with one. I think you'll find as you get older, the truck camper and all the work with what you're looking at doing will get weary. Now, a home base and long trips of a few months is another thing altogether. Is keeping a home base, maybe somewhere else than Seattle, in the cards?
Maybe at least look at a non-slide camper if it's just you. You'll save 100's of pounds, complications, and money if you can make due with a lighter, simpler TC. You'd have to do less or nothing to the truck either.
