There are a few ways to skin this cat.
First, don't buy a raft expecting to fish more if you are the only one who knows how to row.
Second, remember trust falls? Well, putting your friend/family member/co worker in the rowers seat is the ultimate trust fall, no matter what body of water. You'll be shocked at how quickly they'll ram rocks, go into strainers, lose total control of the boat.
From personal experience, if this is your first time owning an inflatable, buy a used inflatable if you can find one. These things, if properly taken care of will last a very long time. At the same time, if not properly cared for, it's easy to mess up a $3,000+ brand new purchase pretty quickly. It would be ideal if you can find an operator selling used rafts. I feel like there is nothing I can do to a used operator raft that hasn't already be done to it and realistically will never hit the water as much as it did or as hard as it did while the operator had it in service. And don't shy away from a used raft that may need a little TLC. Repairs to inflatables, like valve replacements, non-air holding patches, wear spots are fairly easy to undertake and usually don't cost much. There are only a few deal breakers to be wary of like blown baffles, sun rot, mildew, bad seams. Which is something to note if you intend to fish with friends who don't know how to row, repairs are relatively easy.
For companies, NRS, Rocky Mountain Rafts, Hyside, Aire, Moravia, Star are some of the big players in the raft world and I'm sure I'm missing a few. They all use heavy duty materials with a few nuanced differences in design, material, type of valves, shapes. As long as its a quality brand with easy access to replacement parts and repair materials, you can't go wrong. If budget is important, look at the NRS Outlaws and Rocky Mountain Rafts.
For frame, go simple to start. I would even recommend waiting to buy all the frame parts if possible. You can make a simple frame out of spare 2x6's, toss on some oar towers and oar locks and you'll be able to hit the water. Over a few trips, you'll realize what you like/don't like so when it comes time to buying an actual frame, you won't waste money. If you are a DIY type of guy, you can make your own frame pretty quickly with speed rail fittings, fence posts/aluminum pipe, and some spare wood.
Not sure if you'll be able to demo any rafts in the immediate area. Perhaps you can ring up some local operators on the Shenandoah, James, New, Gauley, Upper Potomac, etc. to check out what brands they run and if they have a few size options to see what you may like. I've heard that a few companies will bring rafts to Gauley Fest and let potential costumers take them down the river to test them out.