There's one thing I've always liked about WMP and RealJukebox (not sure about RealOne) over MJ.
They both seperate audio from video.
For instance, they will have their tree with the Media Library (or whatever they call it) and beneath that they will have Audio and Video, and then beneath those they will have whatever view schemes there are. I would love to see this in MJ.
Audio - where I can create Artist, Artist\Album, Genre\Artist\Album, Year\Artist\Album, etc.
Video - where I can create Artist, Genre\Artist, etc.
Images - where I can create Album, Genre\Album, Year\Genre\Album, etc.
That way everything in the Media Library is kept nice and neat. I know that I can do this all myself using the Search Criteria of View Schemes, but then it gets really messy really fast.