Have you thought about using one of the bean mounts like this:
Amazon.com: Line 6 POD Mount: Musical Instruments
It mounts to a mic stand, so you don't have to bend over to make changes to it.
If you happen to have (or can find a cheap) FBV shortboard, you can use it just like an XT/X3 live.
Also, keep in mind, you can add a bass expansion pack to an XT and it's the same as an XT bass (except you'll also have all the guitar side amps and cabs). With the new HD stuff out, you can probably pick up an XT for fairly cheap. If the new HD units had bass amps, I'd sell you mine, but until then, I'm holding onto it just for the bass stuff.
I believe that the X3 has all the same bass amps, cabs, etc. as the XT Bass/Expansion pack. They may be slightly better in quality? But, I'm not sure on that... Although, I think the only real advantage the X3 had over a fully loaded (all expansion packs) XT was the ability to run dual amps at the same time.