I've seen all endings (apart from the train ending, I need one more wallpaper for it). But since the piggy bank gives me 92 Yume, then there must be something wrong with the mingames. The only one I haven't played yet is the color-matching Space Invaders-like game (with the most depressing music ever...), but I didn't play much with Gimmick Runner either (I can't really figure out what to do there).
I'll check them out and see what happens.