I’m switching the status to Partially Done.
The request for a Preview Team is still in the works. No new information is available at this time.
Team Discoverability is still being worked upon, no details are available at this time. If you support this idea please navigate over to the main topic and vote for it! https://microsoftteams.uservoice.com/forums/555103/
Change Prompt: this has been completed
Adding any emoji as a reaction remains under review.
I am marking this as partially done to let you know a new reactions bar with Like, Heart, Laugh, Surprised, Sad, and Angry has begun rolling out to all users.