hakko, I know you clearly stated that you don't want to deal with UI, but I think these fall under the functionality side of things:
-Clickable artist name in the bottom playlist frame that brings you to the local artist page (i.e. not last.fm artist url). I frequently use the "Play artist radio" functionality and discover some song by some artist that is new to me. I would like to be able to click on that artist name and be able to see the other albums/songs I have for that artist so that I can use the "Play top tracks" functionality and determine if I've found my new favorite artist or the next one-hit wonder.
-Ability to star/love/whatever-it-is-called tracks from the bottom playlist frame. I did mention this before and agreed with your response that the frame is so messed up you would rather blow it up and do it again rather than add little band-aids to it. However, I saw your other [feature request] post to start syncing these starred tracks to last.fm so I thought I would bring this up again. The most logical place (IMHO) for the star to be is in the playlist frame as I don't know whether I love a song until I've actually listened to it.
Regardless of your response to the above requests, thanks again for MC. I find myself, family and coworkers listening to hours more music daily than before due to the ease of discovering new music. Really great stuff.