It might be worth checking out the different PRS models. The Custom 24 is the most common model, which can also be had in a 22 fret version. There is also the single cut which is the LP body style. The Mira is really cool, which is 22 frets as well.

Only the Cu24 and Cu22 have trems as I recall...the single cut and Mira have fixed bridges.

FWIW, I stand when I play all of the time now and I find it more comfortable than sitting. I'll only sit when I'm in the initial stages of learning a new song.