I'd say the best way to fight a Jagdtiger is just not play into its strengths. Don't, for instance, buy a lot of Jacksons to fight it. A Jagdtiger can't fight infantry at all and it can be swarmed by large numbers of fast and cheap tanks like M-10s and Cromwells.
Still, there's no getting around the fact that a properly protected Jagdtiger is incredibly powerful in 4v4s. Might be a balance issue but not a very big one imo and only in big team games.
Also, I'm really not sure how you would redesign this unit. imo the Jagdtiger does exactly what it's supposed to do - act like a mobile PaK43 with heavy armour - and not a lot more. Maybe a
slight range nerf but that's about it.
Oh yeah, and I remain unconvinced that the crew shock mechanic is actually a good idea. I'd rather see it get removed and the Jagdtiger get a health nerf or something.
You don't seem to be familiar with the HE ability at Vet1. It has a 125 range and it bascially counters it's counter: AT guns.
Bahahaha. No.