Kathy, Thats very helpful, thank you. I do think its a little odd/unintuitive that this feature is a separate tab from Messaging. There are still some ways that the Slack UI is both simpler and more capable, and it would be nice to see WebEx trend in...

I see this thread is a couple of years old, but the items have not been addressed, so I'm adding one here. In Slack you can arbitrarily drag contacts up and down in the list and create categories. "Favorites" and "Other" is really not good enough.