As for what
genres seem most appropriate:
I tend to create long, rhythmic, groove-based tracks with improvisation on the top. There's elements of jazz, reggae, and krautrock, but I also love listening to post-punk, so I'm always trying to inject a raw, rock-based feel into it as well. Some of the biggest influences would be Fela Kuti (afrobeat), Can (krautrock), Miles Davis (jazz), and Shriekback (post-punk).
I don't like purely "electronic" music very much (techno, drum-and-bass, dubstep, etc.) so I do NOT want electronic-sounding kits; I have enough of those with Battery 4 anyway.
Because my songs tend to be long, I love having kits with lots of drum sounds (toms, bongos, etc.) which can add variety and texture. I prefer to use
one kit per song, rather than multiple kits (a standard kit for kick/snare/hat and a percussion kit for toms/bongos/effects). So, even if a kit sounds awesome, but doesn't have much variety, I probably won't use it.
As for the MIDI packs and loops and stuff, well, I almost never use other people's loops, because I like to play everything myself. I wouldn't mind browsing some loops as a learning experience, though. The reggae ones might be cool. Anyway, I'm not worried about which MIDI packs I choose; it's the ADpaks which concern me most right now.
Does that help clarify?