Currently we have Teams defaulted to show you the first (up to five) channels ever created. If you want to add more channels to your left rail view, just click the ellipses next to the channel name and select “Favorite”. When you favorite the channel, it will then be “pinned” to your left rail under that team name.
Try that and let me know if that meets your needs!
An error occurred while saving the commentAnonymous commented
I agree, what a pain to have to do this. We've just deployed Teams and I'm already reconsidering Slack for this reason alone.