Custom Colours for each team
We've just adopted teams after trialling a few solutions including Slack. One thing I did like on there is an ability to customise the interface for each team available. This is really useful if you have a set of corporate colours (preferably as HEX or RGB codes) for the background, text, selection etc rather than just the standard purple and white. Bonus points if you can allow custom logos too to really tie it into a Team's specific brand and make it their own.
Marcelle Donald commented
Please add Colours to team/channel rows — in the app as well. It would make it easier to not accidentally post in wrong group/channel.