Call me lazy, but I think a first long tour is worth taking on an Adventure Cycling route (like the TransAm). AFter that, you can enjoy the long nights of winter as you research on the web. Road surface? Traffic? Sight lines and shoulders, at least in the mountains? Services -- water, stores, restaurants, rest rooms, campsites, bike shops, post offices if you need to have something mailed or shipped, motels? "Attractions"? Local color or history?

What AC gives you is a pretty good route (not perfect), all of the above for that route, and, at least in the east, a variety of choices. One of the problems is trying to figure out where you're going to end up the day after tomorrow. If you've mapped out a route and guestimated your stops, do you have backups? While you could try to map out all the available services, etc., along any given route, that's a lot more research and data than I'd want to collect, sort, and carry. Some days 30 miles is a hard slog, and some days 60 is a short day. Within the linear AC route, you'll have a good selection of where you can crash, and where you can push.