1- Both. OP on their infiltration, UP on their commander. AI performance changing depending on patches. Badly design and implemented.
So their where not actually causing faction balance issues only diversity with in the faction issues.
Did they need a changes? yes.
Did both units need to lose infiltration? no.
Can their current implementation be improved? Yes if patches stop focusing on fire power and start focusing on utility.
2- Depends on the power level of the infiltration. Infiltration as a concept and implementation is just cheesy. Just take a look at the only real infiltration unit which remains, the Partisans.
Storm trooper, airborne guard and Inf. commandos are also infiltration unit.
I would argue the partisan are semi decent and the commander is problem. As for AT partisan they are problematic but for other reasons.
3- If they spawned with rifles, with grenades on cd, no. But at that point what accomplish infiltration? Gaining a garrison? What's the cost, more coding and complicating things by giving them 2 upgrades, one to buy freely 2 STG and a 2nd one after tech for another 2.
That is the point of airdropping them? So that they can die by crushing to world objects because there are no beacons? So that they can be annihilated during the drop?
If USF paras are designed correctly as and airdropped units Fallj should follow that desing and get more entities.
If ST are correctly designed then fallJ should follow the same example and and be an infiltration unit.
Now the take the worse of two worlds and OKW are left with no infiltration unit.