From what I have seen, used and compared to other indirect artillery, yes, it is broken. It misses way too much and requires the pwefer to come dangerously close range to hit something decently.
It will annihilate quickly anything it targets as long as you don't try to use it into FoW at max range.
If you can't hit anything, its because you're shooting into the FoW at max range.
That's how ALL indirect units work.
Axis fanboys praise katiusha all the time, being completely oblivious to the fact that for it to actually hit what you want, you need to put it at range ~50 out of its 160, but people actually do drive up there.
Do the same with pwerfer and you'll see the only thing that needed a fix was how you used it.