as a guy who feels the need to embrace the future, I'd want AAC file support. Last I checked the DRM free files from itunes were aac files rather than MP3s, not to mention the higher quality and no limit to stereo. (I'm looking forward to the day I get my techno music in true 4+ channels)
I'm down with jazz, but I think the music fits well enough for overland music. I'm anxious to hear the battle music though.