I think I finally have a good idea that would be easy(ish) to implement in CDpedia. I have been frustrated because there doesn't seem to be a good way to catalogue Box Sets. This is a particular problem if it is a large collection. I am currently cataloguing King Crimson's "Road to Red" (22 Discs) and "Starless" (27 Discs) and there is no way to indicate where each performance was recorded. Currently I am adding that information into the title of the song. For example "Easy Money (Live at the Stadttheater, Augsburg - March 27, 1974)" But that makes for a ton of extra typing and it sometimes means I have to retype the titles into my iTunes library, again more typing. There are approximately 275 to 300 songs in just one of the these box sets and you can see how laborious the process is.
Here is my solution: under the Tracks tab you already have Artists and Composer columns that can be added to the track list. Why not just include the possibility to add an Album column?