Song Selection is TERRIBLE.
I have to give them some credit though, it's not as glitchy as the fist Ultramix, there are some fun mission levels. I would, however, like to hear some songs that don't have anything to do with where babies come from. You might think EVERY song in the game is great, but unfortunately there are few I can stand.
When the core of the game is unappealing, it tends to bring down the whole experience.