Sorry boys, soviet howitzer can do that, 120 mortar can do that (of course not at the same scale or as often as wurframen can do it), B4 can do that. AND they do that for a faction that has no fuel penalties.
So when I'm thinking Wurframen is fine, me and alot of people around here, I really don't think this sounds biased even if it would be.
It's a unique unit and it's intended to be this way as most of OKW vehicles.
If it will be nerfed and ISU left as it is, that will be a huge mistake. But this is quite possible to occur.
1)
Soviet Howitzer: Sometimes I forgot it exists because nobody built one since beta, but it can't move, you can guess easily its max range and it's
easy to retreat after the first shell lands. You should be really unfortunate to lose a full squad with the first shell. To add up, it is
doctrinal. Huge AoE, but crappy accuracy.
2)
120 mortar: It has been nerfed from its former glory, I doubt seriously it can now wipe a full healed and vetted unit with just one shell. Usually it wipes wounded or maimed units. Even so,
you can always retreat when you see it firing. By the way, it is also
doctrinal and very easy to destroy it flanking with infantry. Small AoE, terrible accuracy
3)
B4: Slow as hell, and yes it can wipe squads if you forgot about them and they stay static. Even so, the unit is static like a howitzer and easy to take care of. Guess what?
Doctrinal too. Pinpoint AoE.
Stuka: mobile arty, you can't counter barrage it. It is
not doctrinal, you can always build it. Usually there's
no possibility to retreat for support weapons. Unit annihilation garanteed in 95% of cases. Huge AoE, 100% accuracy.
Don't you see that usually potentially squad-wiping units are static, with bad accuracy and easy to avoid and counter? Stuka hasn't not any of these flaws, being its only counter to suicide a T34 in order of killing it.