Put me down for carpet. Easier on the feet, and has sound deadening qualities.
I'm at the beginning of a major rework of my train room. The old layout is pretty much gone, except for a few strangler pieces. I tore out the old carpet as it really needed to go! I got lucky in that the place where I work is renovating large amounts of office space, which includes replacing the carpet squares. These are 2x2' industrial grade carpet squares with very little wear. I asked what was going to happen to them. The answer was a land fill. I asked if I could prevent a hundred or so of them from that fate. The answer was "Yes!" I carted them home, cleaned them up, which did not take much, and installed them. I think they look great!
Don't worry about the wall. I have my work cut out for it.
Chris
LVHR