Not as joyfull, but somewhat similar, deals with relationship with an idol, White Album. Season 2 is currently airing too.
For some reason, princess jellyfish comes to my mind also.
Beck deals with music also, but it's not on the same kind of tone. It's definelty slightly darker, and doesn't only involve girls.
Nana also deals with music, although it's more complicated. Good story though, you'll get hooked.
As of your to-watch list, nothing in there really marked me, Seto no Hanayome (something like that at least) can be funny at first, but that's about it, everything else left me a mild impression.
