Due to the semi exclusive nature of the ass guards (HT fuel cost) I'd like to see them as LITE officer style units. Maybe vet 1 gives activated Aura like ost arty officer has? Something that if you lose the squad it makes you consider calling in another and something that makes the fuel cost call in possibly more than just a one time shock cavalry doc slot.
That's an interesting route to take. You could go even further and do something to the HT to distinguish it from the stock one. Give it medkits at vet 1 or something
I like the idea cause you're right it already has an artificial limit of 1