This has probably been brought to attention, but in my opinion, any customisation of the search function would be constitute a big step forward.
More precisely, I would love to be able to search a CD by catalog number. I understand that not all albums have that much metadata, but a lot of them do, and it would be a great addition for classical lovers (and everyone else no matter their musical tastes) looking to find a particular interpretation out of the 150 interpretations showing up in a typical search.
Thanks for reading and sorry for my mistakes, as english is not my first langage.