Source on the .9 received damage?
Not sure about the source but it's legit.
Rangers take reduced damage, which is why at Vet3 they like from The Matrix, practially Bullet-Proof.
On topic, I can say giving the Thompson Upgrade something like the lower RA Volks with MP40s receive would be good, but it would make it the prefered upgrade. Thompsons to deep flank and wipe stuff without any RNG involved just fits the USF plan so well. Rifles being so good all game long is the reason you don't see Paratroopers, also considering only Airborne gets the Thompson Upgrade, which is usually a latepick for the P47s and Pathfinder scouting.
I do love using the Paratrooper Dodge Bulletin to equalize them with Riflemen.