Ability to schedule meetings in private channels (rather than just 'meet now')
Not useful that you can not easily schedule a meeting within a private channel, yet this is available in standard channels.
Very Important Need! This is already being discussed here (https://microsoftteams.uservoice.com/forums/555103-public/suggestions/40064734-option-to-schedule-meetings-in-private-channel)
Please go vote for this feature!