A friend of mine just bought a Cougar 230trs for his 10 year old 1/2 ton Tahoe. I think it's around 5K dry weight and is really a lot of trailer for that weight. The TRS is a toy hauler which I'd usually rule out since I just think of a garage full of ATVs and stinky gas cans when I think TH. But this has a nice slide out the back king bed and the "toy" room is really just a nice place to throw bikes and gear and doubles as a bunk room (probably not as big a deal for you with the truck bed).
In any case, I haven't looked at 1/2 ton towable RVs in years and was really impressed with what's out there. The manufacturers are really putting out a lot of cool floor plans these days.
After years of RVing and having to change many times due a lack of planning, the best advice I'd give you is to spend a lot of time..... A LOT of time on the manufacturer's websites looking at floor plans. Any lot in town just wants to sell something on their lot. It's pretty unlikely that even a big dealer will have the perfect RV for you.
Check out Jayco, Keystone and Forest River. All 3 have numerous sub- brands and it's really fun to look at what's out there.
