There's only two glaringly obvious things I see need changing in this game. I'm sure there are more smaller issues at hand, but these are the largest that need to be addressed by Relic sooner rather than later.
1) ISU-152 needs to be reversed to its previous state. I used it a lot back when no one used it, and thought it was just fine. It still wiped infantry squads occasionally, and it could damage most axis tanks, even the elefant, though it didn't penetrate every shot 100% like it does now. This needs to be fixed. It's scatter should be nerfed to how it was before. Overall, it's just a gamebreaking unit presently. At vet II, it has a 6 second reload! 6 seconds! That needs to be adjusted asap.
2) Soviet TM-35 mine - It should not be squadwiping fresh, brand new panzergrens / grenadiers. This is simply unacceptable as a tradeoff - 30 munitions to kill an entire squad? Its AI needs to be nerfed into oblivion, with perhaps a slight munitions increase to 35 or so. The advantage should be that they are cheaper than other AT mines, but have the disadvantage of being set off by infantry. They should remain an AV mine first, and have a very small AI capacity.
Also, on a side note - this Katitof guy needs to stop shitposting in every thread he enters. You have a right to your opinions, but every single thread I see this guy post in devolves into back and forth nonsense, "L2P" "1v1 me u bitch" type antics, etc. There's also the fact that someone that has barely played 150 matches total (he's not even rank 100 yet, almost a year after release?) is dictating that their view of the game superior to people who have thousands of matches played.
You spend more time posting on here than actually playing the game. In fact you have over 7x the amount of posts here as games played.
The 100% penetration you encountered is most likely "just your luck (RNG)" because I've never seen the new ISU penetrate the elefant consistently without dying first. I've used the ISU vs elefant and does not penetrate the elefant on every shot. Deflects first shot and penetrates second shot, and pray it will keep penetrating or else the isu will die to elefant. When I encounter ISU it's pretty simple get and elefant. Most people would want to use elefant with tigers but I like using the Tiger Ace with the elefant and I find it to be more effective than multiple tigers in its feeling of ease of micro and its accuracy is legendary, it wipes squads on retreat as if they weren't retreating at all. I do agree that the ISU needs a nerf on its AI capabilities. I repeat again if the ISU's every shot penetrated your elefant then it is likely your luck. You didn't sacrifice enough goats to the RNG God MVGame.