Heh. I will admit that there are some I haven't gotten around to playing. (For that matter, there are some I haven't gotten around to putting on the list...)
But I do buy them because I want to play and experience them. I wasn't sure from your post whether you were actually playing these games... I guess I just can't understand your goal of "collect[ing] every music game made on home consoles." (E.g., I can't imagine any serious music gamer ever playing "Dance Praise.")
For that reason, the only series I have "complete" are Pop'n, IIDX, GF/DM/KBM and now DDR. The only others I really want are PIU (those are actually for PC), Beatmania 5key, {Vib, Mojib} {Ribbon, Ripple}, and Karaoke Revolution. Maybe I'll get into Taiko once I've played it more, but for now it just doesn't motivate me. And I don't get games that I won't enjoy playing.
Of course, one-off loopy music games (like Goo Goo Soundy or Rez) are a whole different ballgame, because each one is new and different and interesting (or at least has the potential to be so).
I have no idea where I'm going with this. Good luck in your quest. Let me know if there's any way I can help you out.
