Currently, the "Add Reviewers" popup lists potential reviewers in an order that I don't understand. It's not alphabetical, it doesn't appear to have anything to do with people who've recently interacted with the files in the PR, or even the repo itself. I simply see everyone in my organization.

It would be helpful if "relevant" people were at the top of the list, however you might define "relevant". Perhaps that's a simple local cache of previously-selected users; perhaps you would be able to use a GitHub API similar to the one that the GH site itself uses to suggest specific reviewers based on people who've edited the relevant files.

If nothing else, I'd prefer to have the list of possible reviewers sorted in alphabetical order (as seen in the lower section of the GH screenshot above) instead of the seemingly-random order that I get now.