Well, you could have something like one hotkey for each member, then aim with your mouse, press a certain button and a drop down menu opens with all available commands, when you select one (drag selection with mouse and release menu button for example) the order is issued to the selected member(s) at that location your mouse pointed.
Otherwise voice recognition.
Mil radio comms are fairly easy to learn since they are made as simple as possible... "One, crouch, cover house at 6 o'clock" or "All elements, follow leader, wedge formation, danger" see how simple that would be? ;)