You could ride for the whole week at Afan if you wanted to, there are 2 centres Afan and Glyncorrwg. They are linked together by a cycleway this is pretty handy ( afan MTB trails-google maps sorry I can't link it for some reason) shows how the trails link up. There is camping at both centres Glyncorrwg has more facilities for instance can get an early breakfast at the centre, tho fees are more expensive £5 per night FFS extorcinate !

It would nearly cost you that to park for the day. I known you like your riding to be on the wilderness side, so the skyline route would be probably your No.1 choice the other routes are more the usual trail centre stuff. Is it worth it, well I could think of better places in Wales to ride but for a flyer and to have everything there and close you could do a lot worse. Sorry can t help with the B&B.