Make "frequently used" sticky in searchable dropdowns

I was thinking this might be especially useful for teams with many users.

I assign to-dos and write comments to the same group of about 5 people. Being able to search and select quickly instead of having to scroll through many is great. But sometimes I start to type the first few letters and another team member's name pulls up and I accidentally select that name. It would be nice if you could somehow make the most frequently selected items from these fields "sticky" so that you can choose who to assign things to even faster. :)