Follow on medics -- that's a great use for the XO unit. I've just had them tagging along with the company command, which also doesn't do much if it isn't involved in spotting for artillery.
I think this is what I have begun doing after losing a few HQ units.
SQUAD********SQUAD********SQUAD
*************Plt HQ
The pitchfork thing.
I leave the mortars way out on the edge of the map. So I've stumbled onto some of it.
I did not know that we ought to keep within 100m of HQ for visual, or 50m for voice, etc, so thanks to Blackcat for that. I just realized you could check distances with the targeting tool. That should be easy enough.
Last question for now -- is there a way to attach a MG unit to a platoon if it didn't start with it? This was pretty easy in CMx1 as I recall, but I haven't run across it for CMBN.