The latest release of Launch Center Pro supports lists. You can read the release notes or Federico Viticci's extensive post on MacStories for details. The gist is that if you find yourself entering the same terms over and over again within a prompt, you can instead choose these terms from a list.
I've written an Instagram action that lets you jump to one of your favorite profile pages in the Instagram iOS app. Just tap on this link while you're on your iOS device to install the action. It looks like this:
Every username is separated by a pipe (|). Just substitute
username1 with your favorite profile username,
username2 with another, and so on.