I admit it's tougher to gun in one now, but that has two sides to it... Always hated getting torched by them from the air too... so I am glad to see the turret speed corrected.
For me, I never used the Wirble that much... mostly the Ostie (whose turret speed has also been reduced)... and mainly as a town assault vehicle. Air defense in them has always been secondary for me. So I will still keep upping in them, and still using them to wreck towns with. And if the pilots are foolish enough to come at me head on when I am in one, then they will go down just as easy as before. It just means that one Flakpanzer cant defend on his own as easily now... a little teamwork is needed.
Yeah, the turret is weak, but it's open... so it always will be weak. I have taken shots in the turret and not been damaged... it just depends on the angle.
It will just take some getting used to.