Ubuntu bugs me a bit just because I don't like its package manager and it installs a lot of extra garbage I don't want or need. And both Unity and Gnome are annoying………then again, I'm quickly becoming one of those dwm assholes. I'd never use it for audio tasks, but for most of the rest of my life, it's awesome………and audio stuff doesn't run on Linux anyway, so it's a moot point.
I'll look into Proxmox. Xen is the one I've read the most about, and it's probably going to win. Well, I guess technically EXSi is the one I've read the most about, but I don't feel like going that route.
I still haven't bought it just because it seems like a waste of a computer……but I can't scale it back and accomplish what I'd want.