This is such a personal decision. We have had all varieties of RV's and they all have their pros and cons. We enjoyed them all. Our only 5th wheel was 37', with two slides and we loved it.
Our personal favorite was a 30' Class C motorhome, and if I were traveling alone---that would be my RV of choice. I want two slides, and a walk around bed. I've been reading Forums for a long time, and there is not much comfort in any couch or gaucho that makes into a bed, and most dislike having a bed they must clear away daily. We've had an over the cab bed, I prefer an entertainment center in that area.
We seldom eat out, I enjoy cooking, so a roomy, plenty of countertop kitchen is needed. I'd like a microwave/convection oven. I have never used the oven that comes in our RV's, other than to store pots and pans in it! :)
Look for storage, storage, storage, both inside and out.
Check the shower and commode for leg and arm room. DH is 6'6" and needs room.
Buy the largest a/c available for your unit, two in larger ones. Same with gas/electric waterheater. An all weather, well insulated unit is good.
Personally, I think your desire for a fiver is a good thing, and feel you'll enjoy it!
Welcome to our Forum, and come on back often, don't be a stranger!
Have a wonderful day!
2007 32' Jayco Eagle Trailer