After much Zen meditating (or as normal people say, drinking beer), I've decided aluminum framing is the way to go. Cheap(ish), zero welding, 1 bar should be enough to do the entire structure and then some, connectors are there, connectors are there to reinforce too. Mounting brackets for everything. Basically, it is perfect. Now I get to buy a drill press and band saw for my apartment too. Power tools, every man's weakness.