I have a feedback for the ZeroTier app 
Please add an option in the app, on the network tab, where we can right click - Add metric for this network (adding metric “1” for the selected zero tier network).
Me and my friends always do this manually in Windows, to be able to find each other on LAN in older games. So this would be a super nice QoL feature to have, if possible Especially since we often disconnect and reconnect and everytime we do that zerotier creates a new network for the connection 
Implementing this feature should not be too difficult. I already possess a command for it on both Linux and Windows, so integrating it into the app with a command that assigns the selected ZeroTier virtual network to metric-1 should be feasible ^^