I have installed:
- discourse-cakeday - nice to have
- discourse-spoiler-alert - must have
- discourse-user-card-badges - totally frivolous fun
- discourse-yearly-review - nice to have
- docker_manager - standard distribution / must have
My personal preference is to make the image for the Welcome badge fun (I have a fleur-de-lis image) and I use that badge on my usercard. All of the badge images on my forum were selected with an eye for the user card secondary use. The Certified (epaulet image) and Thank You (rainbow) badges are most popular for that.