When you have a large, or very mixed playlist, you probably skip a ton of songs, because you are not in the mood, or perhaps the people you are listening with have a special taste. Instead of having to create a ton of playlists for different moods and such, why not simply sub-categorize an already existing playlist?
I suggest you could add one or more "colors" to a song. Not to make them look special in the playlist, but to make them part of different categories. This would enable you to shuffle play only with certain colors in mind, where you would perhaps get a drop-down selector wheel, or the likes thereof.
- Maybe you only want to hear your "red" rock songs?
- Or maybe you want to hear your "yellow" hip hop and "purple" pop?
So you would be able to shuffle play as many, or few colors / themes as you like, and also if a song fits multiple themes, you could add as many colors as you like. I think this would eliminate the need for many playlists, and make creating playlists more interesting, and easier.