So if you open Recents in the sidebar it's likely it's full of files you have no idea you recently opened. It's most likely that you didn't. We can make Recents more useful by restricting the last opened date, and make using it more convenient. This is how:
- Open Finder, then Recents in the sidebar.
- From the cog menu, select Show Search Criteria, add a criteria via the plus button.
- Change the filter name to Last Opened Date within last 14 days and press Save.
- Name it My Recents, and enable Add to sidebar.
- From the sidebar, drag the smart search into the dock next to the Trash.
- Optionally remove the recents icon from the sidebar. You can restore the item via Finder > Preferencers > Sidebar by dragging it back in.
As a bonus tip, update the icon for the smart search (just like any other folder and app) as follows:
/System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/ and search for "Recents" to find the current Recents icon, or choose an alternative.
Right click on the My Recents icon in the sidebar and choose Get Info.
Drag the preferred icon from the folder into the icon slot in the top left of the Get Info window.
This changes the icon in the window title, but I haven't found out how to change it in the sidebar.