I really don't get what is so great about that sort of anime (drama and music are a weird combination to me) , anyway I think you might like 'Shigatsu wa Kimi no Uso' (if you didn't watch/read it)
Grand Blue because all your titles have blue in it!! Seriously though, Grand blue is a funny slice of life of a bunch of college students in a technically diving manga
If you're about the music romantic drama and all, try Nodame Cantible. As a classical musician I can tell you it portrays musicians the best, and their posture and playing doesn't make me puke my guts out.