My shows were Tues nite and Saturday nite.

College radio, and they didn't know what they were getting themselves into. The only non metal I played was Neil Young, and then only one song: Sugar Mountain. There was one frat house that always had my show tuned in, and they'd sometimes request that song. Even during my Metal Hellion Years I could still appreciate that Neil was the man.
A good sound system should be able to play whatever you throw at it, but it does have to be able to crank out the bass and dynamics in spades if it even hopes to reproduce the slam and bombast of heavy metal. I bet a speaker like the VMPS Tower II would be great for hard rock.
Resolution is also important; a lot of heavy metal records are very dense mixes, with lots of information vying for driver space. If the speaker can't resolve complex lines at high volume, then you do get the "moronic noise" that people often accuse the genre of being.
I'm pouring over my collection, Nathan, trying to decide just what type of stuff I'd put on a sampler. I get the definate impression you're more into the fist-in-the-gut stuff, right? Most of the stuff I listen to is a little more melodic, and more "produced" than the stuff on your sampler. Of course, bands like Pile Driver and Venom are exceptions to that...