Valvestate amps were the bane of my life when I ran a recording studio. If someone came in
with one I knew that I would be in for a day of horrible fizzy guitar sounds that the
owner would expect me to magically turn into chunky powerful sounds. Personally I'd
suggest that you use one of your Pods.
I'm not sure whether sound barrier mat
will have much of an effect on the floor unless you add another solid layer above it.
JRP Music - Audio Mastering and Restoration.