Panther wasn't that much of a failure.
Jagd[tiger] is a buildable replacement for the Kettenkrad... It can cloak and cap points.
loads of tanks had problems, the Panther was the most unreliable German tank of the war apart from the experimental tigers like the Sturmtiger.
That is not actually true. I have read plenty things written by German Tankers that have said the Panther was as /or more reliable than the Panzer 4.
I heard the panther was more reliable than even the P4 but it was far harder to change parts/repair when it did break down?
The German tanks were best used defensively. e.g the only major German offensive in the west (the Bulge) was lead by Pz4's cos they were more reliable