Layout has as much to do with it as actual length. I had a 28' and a friend had a 24' at that time. His felt larger because of the floorplan. 6 ppl fit comfortabley in his where mine was crampt with 4. His shower was larger but I had much more storage. Mine was a bunkhouse with front queen bed while his was just one big open room.
I think I would stick with the 1/2 truck, stick a 5th wheel hitch in the bed and get the largest / heaviest 5th wheel that could be legally AND SAFELY pulled with the truck.
IMHO 5th wheels give you lots more basement storage for your rods'n'reels, shotguns, bow'n'arrows etc etc..... Also again MHO they tow more stable and safely than bumper pulls.
And once at your destination and unhooked, you've got your reasonably sized truck to run around in.
See new post "I Found It" dated 5/30 for the next chapter of this story...
2007 Titan LE with the Big Tow Package - frequently a really cute 8 year old in the back seat
1994 Terry 19N
2008 Suzuki GZ 250-Response to 3/4 Life Crisis
First of all I am sorry to learn of your loss. I would suggest a couple of extended stay Trips. Then if you decide that fulltiming is for you, go for it! I am a Fulltimer as of last Month. I LOVE it!
A slide in trailer makes sense for 2 or more people - more room to pass each other in the narrow corridor btw dinette and kitchen counter. For a single person a 24-26ft trailer without slide is plenty (i.e. 21-23ft actual box length). Especially for a male (my apologies if I assumed wrongly). You will find it huge after your current 19-footer. Two people is a different matter, more closet space needed for partner, etc... Mostly, it's about narrow shape of a typical TT - that's why a slide for a 2 or more people. TT can be very long, but they are all narrow, 8ft usually. And you don't want it longer than necessary either.