I'm a newbie to this also so the only advice I have to offer is my own experience in choosing a rig. In my opinion, the FIRST thing to do is honestly assess your needs and habits in using a camper. Do you really need a slide? It adds weight and complications. Do you really need AC? If yes, do you need to run it while boondocking or only when you have hookups? Do you need a lot of amenities while camping (TV, DVD, stereo, microwave), or are you camping mainly for the quiet and solitude? And remember that a generator is probably only needed for boondocking with AC on. You can run virtually everything else you might want with solar panels (a lot lighter than a generator). These things affect your camper choice.
I think you can do fine with a SRW truck if your needs are modest. And I think you should definitely go with a longbed, because it brings certain handling advantages while loaded, whether carrying a TC or pulling a trailer.
Oh, and another consideration. Don't get a 4wd truck unless you *really* need it. It will add several hundred pounds to your curb weight and also cut into your mpg.