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Basically what Shep said, relies too much on getting Vet and it IS a bug, there is no way a Puma shot is ment to wipe a garrison for 45 muni. Also why would you EVER Get Falls when you can get Obers? Obers out class Falls in everyway and Falls bleed so much man power. The only way in which Falls are better is the fact they have some form of Smoke.
Also Panther has too low HP and too low DPS to compete with most tanks by the time it comes out, especially if you get RNG'd and it misses 2 or more shots.
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Don't get me wrong, I love the Support gun, just for Anti-garrison purposes it requires a lot more manual input then others, you have to aim at walls manually unlike others which can just hit the building deal splash to troops inside and decent structure damage.
Stukas can work I just find it a huge risk throwing your first 140 fuel in to Truck + Stuka, It can work if you go a mostly Manpower army with 1/2 Puppchens. I just find the Stuka very RNG even when aimed correctly, I've seen shots hit across 6+ blob squad and only take a few models other times I've seen it wipe them entirely.
The Jagdpanzer is awesome, great frontal armour and Panther gun but with faster rate of fire, whats not to like? It can also go stealthy at Vet 1 for sneak attacks, if it ever gets to Vet 4 it's first shout out of Stealth is LETHAL.
Yeah US just seem to be a well build army with answers to pretty much any situation.
The only reason I say it's a weak point is because US can just blob at you due to lack of Suppression/AoE, do that against any other army your infantry will get slapped by something or mass suppressed.
As you said, Elite Infantry is what replaces your general armour for OKW or so it seems. But because of the expensive cost and low model count they aren't really durable enough to fill that roll properly late game.
I've played with the Luchs since the buff, it really helps a lot, it means if you run in to a captain it doesn't just immediately die.
Well the Idea behind the caches is, the other factions don't need an extra "fuel point" by building 2 caches, where as the Okw could really do with a way to catch up in income other than the convert on the mechanized truck as that really hinders you in other ways.