When it comes to DPS and DPS vet bonuses I don't really see how they are more OP when compared to Penals, since Penal will probably achieve vet 3 faster and will be more power at vet 3 than PF.
Because DPS is not the stat to rule them all. Performance of units is relative to faction and cost opportunity. For ex: if any faction other than USF had Paratroopers, i bet we would see them more frequently. Same with the commander/tier they are part from.
The problem i see with Penals is the fact that you ONLY get penals instead of a mix bag with conscripts. One could play with vet requirements for sure, but if more, why would i even bother going T1. And if that would be the case, why i would even play SU at that point (unless other changes are done).
If one reads my previous post one will see that imo compared to grenadiers (the benchmark) this unis is OP.
Once more imo has to first set the level and balance the stock units that are available before minute and then fine tune doctrinal units.
Mainline infantry should be comparable not equal.
For instance Riflemen where designed as infantry that is OP because their support weapons where UP. Since the latest patches tented to improve the cost efficiency of USF support weapons Riflemen need to become a bit less OP.
Answering both quotes.
Grenadiers are not isolated unit. They are replaced by Prosttruppen (haha Assault Grens) or combined with Pio/MG42/Sniper/Mortar.
Going back to USF, you can't field support weapons at the same time. By the time you can hit a .50 cal, you are barely ahead of a fast T2 timing. Early on you work with RE/Rifles/Mortar (which was rightfully nerfed). If you are hipster enough, Dodge/AssEngi/Path. When you have to hit Rifles with the nerf hammer, i'll rather it be BARs to make them to be more ARs performance wise -close/mid range-. (this would hit other ARs long performance as well). PD: power also comes from freebies.
I'll say both UK/OKW main line infantry are not an issue early on as much as when you hit critical mass with vet/upgrades.
SU is stack with an old outdated model of upgrades for Conscripts (still shit performance unless mass PPSH). For the early game, you are either stack with Conscripts with upgrades, going T1 or getting T2. You can hit Penals in a different way rather than sheer performance. Field presence early on (build time) and/or the call ins which makes transition to mid game good (this is another can of worms).
Easy fixes like pop, sight and permanent sprint can be implement regardless.
At the end of the day, this is all that should be done if there was any patch in the horizon. You could argue there is some place for weapon slots but as you say, other things are fine tuning.