To keep this to one subject, or feature, I'm using the general term in the title. This was my first desire to suggest about 12 years ago when I first started using serato, before I switched to rekordbox, but I still have the need, upon switching back to Serato this year.
My number one suggestion? Tiny, please aquire mixed in key, and hybridize (merge) that company with serato. Every single needed Library functionality is already possible with mixed in key software, in very very ideal ways. All sorting, labeling, renaming and relabeling, and even sonically improving the tracks that need it with platinum notes, but all built in to the serato library, talking all nicely to it.
The bonus of this move would be every other piece of software both companies make could essentially combine and become ACTUALLY full fledged powerful AND modern up to speed tools, especially as relevant to this post, for large libraries to be managed well all in the same place the tracks are actually used. No offense to either company, as they are both top notch. Just could do each other a real service if they teamed up.