Mitsuda is a fine muse for your music, but if you want Japanese composers, don't discount Koichi Sugiyama, Yoko Shimomura, Tomohito Nishiura (probably my fave), and loads of other people that don't make music for just video games.
One of the more intriguing aspects of Koji Kondo's work for me, was realizing that he to write songs in Ocarina of Time to be played by players on their flute. So he basically needed to start with these 3 notes melodies and then morph that into a full thing. I always thought that would be really hard, but I have no idea, honestly. Maybe it was really easy!