Yeah, I do that. I could see a "lock group" clickable maybe on the left of the portrait list that shows up when you have a group selected. With it locked, moving any unit of a group moves the whole group so you don't have to worry about selecting the leader in the stack of portraits, then if you want to take anyone out you just unlock it, move them out, and re-lock.
Makes it pretty easy and convenient, I think.
