There should be a random shuffle command.  I don't know what key it should be on, if any.

Shuffling a playlist should probably not affect the contents of sections.  That is, shuffling a playlist containing just three sections should randomize the order of those sections, not affecting the order of things in the sections.

It might be useful to be able to internally shuffle sections, but it doesn't really make sense to mix the contents when shuffling multiple sections.  Usually, what one will want to do is splice all sections into the toplevel and then shuffle that.

It will definitely be useful to be able to shuffle regions, however.