Feature request: list popular collections by default

[rmjarvis]

After selecting a repo, one currently needs to know at least something about the name of the collection you want. It will give a drop down list of auto-completes once you start typing something. But if you have no idea what collections are in the repo, it's not easy to figure out what to type.

Suggestion: have the "auto-complete" for a blank Collections field be the 5 or so most popular collections for that repo. If someone wants something else, they start typing and it works as currently. But that would massively lower the bar for people who don't know what collections are even available to type.