Two thoughts I had:

1. I'd like the ability to write info about particular artists that aren't tied to a specific album so that no matter what album of theirs I brought up, I could have access to this common artist info. Some people may just cut-and-paste from All Music or an artist bio from a web site, but I'd use it to write personal opinions about an artist or my experiences with them if I'd met them/collected their music for a while.

2. I'd also like the ability to connect artists. Especially with jazz I'd like to be able to group albums released by "Benny Goodman" with "The Benny Goodman Orchestra," etc. It may seem obvious that these would already be grouped together alphabetically, but that wouldn't always be the case (for instance, linking Phil Collins and Genesis). I'm not exactly sure the best way to implement this, but I thought I'd put it out there.