I think i have to correct some aspects which had been mentioned before. The data mentioned and some of the analysis of it is from an incomplete pool of games.
-UKF: They were used at least 8 times, having a 25% WR.
-OKW: the match up against both USF and SU was fair.
-SU/USF: their match up against OH was highly favoured. OH won 6/18 games (33%) against Soviets and 5/16 games (29%) against USF.
SU mostly went with IS2 doctrines against OH (11/18 armored assault and twice with Shock Rifle).
-OH: T4 has been the bane of diversity for OH, mostly on 1v1. This gives them troubles when we live in a heavy meta. Their is no Puma to save them this time neither for when they are behind in light vehicle phase.
-THERE WAS NO LACK OF OH NOR USF.
OH=40
OKW=67
SU=50
USF=49
UKF=8
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Now going into analysis:
-You have to take into account that if a faction is COMPLETELY OP, it will dominate far more heavily pick choice. Same in the opposite way if they were UP. There is also player preference to take into account. That been said...
-UKF saw almost no play, not because "PRO"s didn't had balls, but cause they had been heavily nerf for 1v1, when the clutch which hold the whole faction has been nerfed (mostly IS bolster) and their strongest units been normalised (Churchill).
Add that we live in a heavy call in meta, and that the call in vehicles from UKF are not all rounders good AI and AT, and then you have your answer.
Players who might had picked UKF in the past (HHans/Jove) didn't do so. Those who favour it didn't make it pass the round of 16 (Aimstrong and Ashabois). Barton tried them once (and lost) and other players who might had brought them didn't participate (CPrice/PaulAd/others).
-OH: if you are playing from behind, you will be heavily strained mp wise, cause the opponent will bleed you by pushing the advantage with light vehicles (Stuart/T70) and stalling into a heavy tank (IS2/Pershing) which you can't really counter effectively with T3.
Puma doctrine is no longer a thing, which might make heavy T1/T2 play viable. The 222 can counter M20 but will lose to anything heavier (Stuart, AA HT, T70) while not providing as much as AI for fuel investment nor AT. In the past, it would had act as soft counter for cost against a T70, but after the rework to 400HP and 222 cost normalised, it's no longer possible.
T4 no longer has OP Brummbar which might make it worth to get in 1v1 and spending all resources in either getting a PV or PW as first units is not viable. This limits the options against heavy armored vehicles.
So what is probably gonna be the focus of attention towards the future:
-Heavy call ins: they are probably gonna get nerfed. Mostly regarding their timing (CP) and maybe cost. The IS2 is likely to get a certain degree of armor nerf.
-SU: probable fine adjustments towards the 7man upgrade on Conscripts.
Everything else mentioned is heavy speculation.
My view:
-Heavies: they should also debate if removing the extended range at vet 2 (either from 45-50 or 40-50) would be a good idea, as this makes 50 range TD irrelevant as the heavy tank can return fire with ease.
-TD: vet adjustments.
Stug: swapping vet 2 with vet 3. TWP from 80 to 160dmg. Spread out 30% ACC between vet2 and vet3.
PV: Spread out 30% acc on vet 2 and 3
Jackson/Su85: tone down vet pen increase to 10% (basically mirroring performance when equalising vet with PV getting skirts)
-UKF: plenty of things to consider in how to improve the faction or making it viable in 1v1 without clutches/cheese.
-USF: hard to say and surprising as most people bring SU as an issue and not USF (which might be the case but most will start to talk about it once all data is released).
-OH: i'm not sure how much more can be done to make T4 viable on 1v1 without making any of their units OP. It might be now the time to test (again) how to reduce OH eternal weakness to light tanks.
The problem with OST is that T3 and T4 is not good?
I hope that very soon the OST will be buffata. I don't find it right that a faction remains like this.