What don't you like about the vagrant? Sounds like it what your looking for. If your back hurts at the 2hr mark it's time for a nice slack full suspension or maybe an exercise program to strengthen your posterior chain. If you just feel like building up a nice new hard tail just for the fun of please disregard my useless advice.
The hardtails I'm interested in are: Trans Am, Dialled Alpine, Evil Soverign, On One 456 and Sinister Ridge, just to name a few. Good luck.