You can't have path finders every were and you only need to be in cover/building for you Rifles to get the sight bonus, which is a big deal if you combine it with rear's in FP's and rifles supporting .50 cal's. The IR Artillery comes in faster than the 155 barrage and does more damage, while also having less spread, and it comes from a mobile unit that can cloak.
The greyhound can easily stay viable late game with it's speed and sight, it just becomes more of a support vehicle that you keep with your infantry and tanks to help clear out blobs. The two paras and 1 AT aren't obviously optimal, but if your floating MP instantly getting 2 airborne squads and an AT is a pretty big deal.
Mechanized is literal garbage, Rifle is as I said, a noob trap that exists to trick people out of their munitions, fuel and MP. And your constant insistence that the priest which is a mobile howitzer is terrible basically means you have never, ever used one. Don't sit it in your base, sit it behind your front line and there is 0 chance he will be able to avoid the shells 100% of the time. Also just force a retreat and bombard his Medi HQ and you can wipe several squads easy.
I guess you missed a part somehwere here when I said, I killed Elephnat with Priests.
"Mechanized is garbage..." I could also say Recon is a garbage.
Greyhound and nothing more. You are trying to say that Paras drop is helpful. But it's not. By this time vetted Obers will wipe them.
And again, try Priests in 1v1. Then we will talk. Or upload a replay of 1v1 game where your Priest is shining.
USF is a micro intensive faction, but if you play well literally the only thing that can stop you is a KT.