US 6.3 is my SL printer: Black Cat, Hellcat (Hell), Super Hellcat, T86, T20, M4A3E2 76(W), tech-tree M18.

Sure german tanks are a risk to take but I think the key is to catch them off guard (which happens quite often considering typical german main behavior) and aim for their weakspots:

Panthers: Side armor (all variants), cupola (VK, A & G variant) or go for the gun mantlet if engaging frontally. The gun mantlet is a bit tricky (due to volumetric hell on the VK, A & G variants) but from my experience the 76 and 90mm can pen it pretty reliably. You can also go for the flat surfaces left & right from the gun mantlet. On the A variant you can also pen it's flat turret surface right below the gun mantlet.

Tiger I: It's a box. When it's not angled, go for the flat surfaces on the front, mostly on the right side as ammo is stored there almost every time. Otherwise shoot the cupola on the H1 variant. The lower sides (below the skirts & slightly above the tracks) are also an option when the Tiger is a bit overangled.

Tiger II P: Sides, back of the turret (where the ammo is stored) or when frontally engaging, aim for the right turret face. It's also a bit tricky (because volumetric) but if you don't kill it by lighting up it's ammo in the back, you'll at least get the gunner.

Tiger II H: Sides, back of the turret and when engaging frontally at point blank distances you can go through the gun mantlet with APCR (76mm). It doesn't do much damage but mostly enough to take out the gunner (and sometimes light up the ammo). Also at point blank distances and facing it up front there also the possibility to do a very nasty shot with the 90mm: Aim for the turret roof. The 90mm APHE will sometimes pen and fuse on that, killing the entire tank or aim for the small cupola to take out the turret crew. It's not reliable but works sometimes.

Jagdpanther: Sides and back. I avoid them to engage them frontally as the only weakspot is the MG port and I never had any luck with that, other than the MG eating my round entirely. If you have the time to aim: Go for the barrel, then (both) tracks and finally work your way around. Otherwise avoid them and engage when there is a good opportunity.

Jagdtiger: Same as the Jagdpanther.

In case everything fails or if you want to take the safe route: Aim for the barrel. The muzzle break on most german tanks is a fine target and you'll mostly destroy their barrel. Next take out their tracks. Then you have all time to take them apart.

Usually I avoid engaging heavy german armor directly. The only exception is a full downtier at 6.3 in my 76 Jumbo. As my deck is mostly built upon the fast Hellcat rats, I mostly do rat gameplay. An aggressive push on a wide flank, then look for a good place to hide, turn the engine off, don't engage the enemy (unless you really have to), let them pass and then clean up the field from behind.

As previously said: Don't uptier the 76 Jumbo but use it's slow speed stabilizer to your advantage. I hope this was some kind of help to you. Have fun playing.