Thanks again for all the comments.
The bass sound wasn't achieved by anything magical - just the dude's bass guitar running in to his amplifier, then out of the amp to the sound card's input. Wish I could take some credit but it's just one helluva' nice sounding bass guitar (musicman, with the huge-ass pickup that covers most of the front of the guitar). It just sounds wonderful through anything you plug it in to.
The drums were also about as basic as it gets - audio technica atm25 on kick, 57 on snare, with two oktava mc012's on overhead. All mics ran through the inserts on the mackie board and that's pretty much it. I definitely had one of the overheads too close to the cymbal. I think I can tame the over-exaggerated crash if I compress the hell out of the overhead tracks before mixing in the kick and snare - if that doesn't work, I suppose I can edit the tracks, highlighting just the crashes and bringing the volume down on them. The key, again, was just a very good player and a very good kit. The dude is a professional drummer, so he knows how to tune it, so that's also key.
I really need to have him re-do the vocals in a dead room. A lot of your comments are right. The room sound is just too much. I added some chorus in an attempt to thicken the sound, but that might just be making matters worse.
Thanks again for the comments and criticisms.