Attack-move is good, but I think a new Guard-move command would be great for Zero-K.
A lot of the time you have some riots that you want to hang around skirms or artillery. You want the skirms to dance and advance as needed (attack-move), and the riots to move along with them so to ward off raiders.
The current options are a little bit awkward: You could give your army a ctrl-move, but then the skirms would not be able to dance. You could just station your riots nearby but then you would have to keep an eye on them to move them forward when the skirms advance. You could give a guard command (normal, alt, or circle), but the issue with that is you would probably do it on one skirm, and if that skirm dies then all the riots are free.
So I think a guard-move command would be useful. How it would work could be the units move to a place and if they find allied units that are not themselves, they guard.
Or maybe an area-guard command where the selected units spread themselves to allied units in the area? Probably a better idea tbh.
