I've noticed that there's no search shortcut in the keyboard shortcut menu and I'm assuming that's because we're given the choice to choose our utility for that particular thing (e.g. ANGRY Search, Tracker, FSearch, etc.).
Instead of relying on some third party (or having to search for one), I think it would nice to somehow get that working in Cinnamon. Not that there's anything wrong with using 3rd party... as this is Linux, of course.
The menu on the panel has a search box but only searches for the items found on that menu. I'd like to think it could be modified to also index files and such on the system.
If that doesn't seem desirable, then I'm sure someone could come up with a better idea than I could.

Anyway, that's my "idea" for what could be worked on. Not a major issue, but something I would definitely find utility in.