Really good work. Thanks.
One thing though, I'm not sure if it still works when one artist and his/her alias has credits for the same role. I know nothing about Bemani, but here are the two albums that come to my mind (for that matter, neither of them seems to be based on the official booklet, I think).
http://vgmdb.net/album/256
http://vgmdb.net/album/15861 (credits based on
the official store).
I think it would ideally show up like
Composer (as Kinuyo Yamashita, Minakuchi Engineering Staff) or
Composer (also as Minakuchi Engineering Staff) in the artist page.