Lark is actually pretty good. It has a counterpart - Atlassian, MS Teams, but it's a little better than both of these yet not as good as Slack. (IMHO) It seems

Lark is actually pretty good. It has a counterpart - Atlassian, MS Teams, but it's a little better than both of these yet not as good as Slack. (IMHO) It seems to be a little better at sharing data to external parties as well, which Slack does not do.