I like using the Guards+mark target+ISU commander when playing as soviet. Generally speaking this unit performs well at AT at max range,it can outrange all the armors except the JT and the pen(230) is good eough,40 more than SU85.
Maybe it could use a slight buff of accuracy vs infantry at max range, but just a slight buff, nobody want the old ISU which slaughters everything back.
The Penetration is horrible and here is why:
ISU pen drop: (260/230/200)
SU-85: (200/190/180)
Overall it's better to go for an SU-85 than for an ISU.
The ISU can't fire while driving. The SU can.
The ISU has less mobility. The SU has more. (turn time being very important in that case)
SU-85 can't be used against Ele and JT but you can simply switch to use other means such as IS-2, or T34/85 tanks. If you go ISU and the enemy goes Ele, its gg in lategame.
Let's assume we are fighting a stationary KT with ISU and SU on long range. Here is the average dmg for each ISU shell and the average dmg for the SU-85 compared to the ISU. (reload for one ISU shell*dmg*chance of pen)
ISU: 1*240*0.53 = 127.2 dmg
SU: 2.5*160*0.48 = 192 dmg
~50% more dmg for SU
Now with veterancy (SU with vet3 is quite common in a good match, ISU at vet2 is not unrealistic but takes very long):
ISU: 127.2*1.3 = 165.36 dmg
SU: 192*1.3*1.2 = 299.52 dmg
~81% more dmg for SU
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And a accuracy buff against infantry? A gun that wipes paks and weapon teams in an insant, no thx.
Sweep/mortar/arty/bomb/nade the mines
roll in with your bazooka blob / AT gun blob / M10 / T34-85 horde, mark target. done.
Mind providing a video/replay for such a case? Because, the whole point of planting mines and baiting with an Elefant supported by 222 is to counter M10 and T34 rush. Bazooka blobs can't act because they get countered by AI infantry (which can not be countered by vehicles because Ele) and a AT gun wall gets ripped apart by Stukas, Mortars, ISGs and Panzerwerfer.
And your idea of taking care of those mines ....