HOMEWORK: Compare Mystic Formula to Final Zone II. Is FZII a better game? I think it might be, which is saying something (since I find FZII pretty mediocre).
Both games offer a chance to play different characters (with different weapons), but, as others have stated, it doesn't appear that the (lackluster) stage designs/enemy AI were implemented with much consideration for the different characters.
Mystic Formula really should have been a captivating game...