One important thing for this would be the ability to do album shuffling that can shuffle a few tracks out of an album rather than the whole album all the time. So going back to what I said before about setting a source for "same/different" slider, you could set it to be "album" and it could perform biasing similar to how it currently does for artist but for albums, so you might have some albums where a bunch of tracks play together if you set the bias high towards same, versus if it is more centered you might have only a few tracks from each album at a given time. This would be very nice to get some more variety while not necessarily blowing through a whole album.
This is also better than just simply setting discs to be defined as albums, which can be used currently to break up larger albums, as doing this would allow the tracks that are played together to be random. If you make discs considered albums and let's say you mess with the metadata to define "discs" yourself to split up albums (as I did), then you're going to have some tracks that will always be played together no matter what when you album shuffle. By allowing other metadata to be selected on the same/different bias slider, you can keep your album metadata integrity sound while also allowing for a lot more unexpected playback which is always great!
As I said before though, this doesn't just limit to album shuffling, you can shuffle with bias for anything:
Artist, Album, Composers, year, or even virtual tags like in my case I said before!