They may as well just add to the drop down menu, in this awful oob they are bound and determined to stay with, a list of all troops of a type. Instead of a contrived drop down, just list the troops. IE: if you have 50 total troops, 50 infantry(20 sturg. spearmen, 10 batannian trained warriors, 20 battannian clan warriors), just list them on the drop down tab. It could work even if you were the head of a combined army with all different kinds of troops. It might be a little tedious scrolling through scores of different troop id's, but doable.
It's pretty much just a round-about way of doing it the old fashioned way, but that's what everyone wants(the old way of assigning troops), and it should be ok with their console-first mindset, which is what this awful oob is all about.