Balance issues must take in consideration the customer game experience. For example, a couple of months ago, who would have consider the M8 as broken? The unit was exactly the same, but nobody was using that commander. Why suddenly people get to use it? 2 different causes imo:
1- The player experience translated in game as Skill has improve since 6 months, people are less dependent of the best commanders choice to win a game, so they can try other commanders with enough confidence to win.
2- The meta is now focused into blobs and counter blobs and this commander proposes something unique and extremely powerful for the USF faction.
http://www.coh2.org/topic/20640/greyhound%C2%B4s-canister-shot
-We lived in a world that wipes weren't as much as now due to indirect fire, tanks or HE shells.
-HE used to suck
-AT grenades from PF and Rifles were useless.
-USF was simple not playable on 1v1 against OKW and a walkthrough against OH if you decide to cheese AA HT.
Maybe at mid-lower ranges things have change, but at top high end i haven't seen too much evolution. Blobbing doesn't neccesarily means bunching all your units together.
You can push on a massive group spread out, using cover, moving injured troops backwards but still fighting etc - to overwhelm a inferior mp force on a sector and them just keep steamrolling or retreat knowing that you have won the mp war.
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OP, it's simple. You add 2 more variables on the equation and the exponential issues are meant to rise up as combination of factors increase.
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WFA as a whole brought the blob issues: "cheap" units with high DPS (including AT dps Volks shrecks) or cost effective mp infantry (1919 + Obers) with a retreat point in the front including healing and reinforce.
If you blob as SU or OH you go back to your base giving up territory.
You can punish it. But when you can't, it's just further increasing the snowball effect.
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USF + OKW are broken on 3v3+. One is useless, the other too useful.
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People praise OH for it's conventional tech tree and options. Some people hate SU because you have to cheese to win because stock units are lackluster and you have access to half of it. Well, OKW is "cheese" on itself by design. You don't cheese with doctrinal units, you do it with your stock units.
Conclusion:
Nope. OKW is not the root of the problem. It's a matter of constant not solved problems which increase due to the introduction on new variables.
When you slowly tackle down big issues, then smaller things starts to come to awareness. If everything was fine i'm expecting MORE Su76, M5, M3 HT, USF MHT, FHT, Mechanized, Irregulars, IR HT, etc threads.
Let's say you somehow fix Raketenwerfer, Volks shreck, Obers, OH early game n USF late game, etc but you add new commanders on the rotation shop.
Ex:
-Assault PG are FOTM, the offmap bomber can be casted on the USF base 1 shotting it
-USF gets Pershing which is an IS2 on steroids. On top of that Calliope which for some reason can use it's main gun.
-SU gets the No retreat no surrender commander. You can't retreat unless you use a commisar ability. This leads to cheese strats. Soviet industry release levels.
-OKW gets Koningskubel, KCH, Flak and zombie Volks bunkers.
Then you just jump from one problem into another.
Another example without adding new units/commanders is overbuff of things. Think of Katyushka patch.