Charleston isn't on that route so I don't see how that is up for consideration. I've stayed at cheap motels there a couple of times, you pretty much get what you paid for.
Haven't stayed in Beckley but driven through. I haven't heard that 1*/4* story about Beckley, and I'd check actual prices to see how true it is, but I wouldn't be surprised if prices are a bit high since it's where 64 & 77 come together. TripAdvisor doesn't show any hotels rated 2 or below, something neither Charleston or Statesville can claim, fwiw.
Don't know too much about Statesville except that I took 77 south onto 40 West in October and there is major construction with very little helpful signage and I was lucky to get on the right exit for I-40. So if you go for that, I'd be sure to get a hotel off I-77 without having to go onto I-40 at all.
Mountain driving through WV can be a bit tense with all of the curves and hills. But, I-77 south of I-81 was a very nice uncrowded drive, so I personally wouldn't mind driving extra hours at the end of the day on something easy like that.
I'd probably make my decision based on how far I wanted to drive, and avoiding an area that seemed way overpriced and any places with poor reviews. I just want a clean safe place to sleep and be back on my way.