One word: production.
The Panther was superior to both the main flavors of T-34, yes. However, it came at several times the price tag, that being caused by a) German over-engineering, b) hurried design and c) *1.5 weight.
So, everything else being equal, a lower production output was unavoidable.
Indeed, if you only take into account the more dangerous T-34, the one coming with the 85mm D-5, the Soviets produced some 19,000 of those, versus some 6,000 Panthers. This means the Panthers can only lose, because, even though the Panther's superbly sloped front armor could beat the 85-ZP's round at average tank-engagement distances, its thin side armor could not – and if the enemy has three of those 85mms mounted in those T-34s, for each one of your 75mms mounted in a Panther, the fact that the 75mms are 70 calibers long will probably not prevent one of the three from achieving a flank shot. Note that even some of the 76.2mms of the previous T-34 models had fair chances of piercing the Panther's sides.
So going for the Überpanzer was all a bad idea. Yes, the Germans would have been better off with something heavier and thicker than the Pz IV, if possible with the KwK42, but not necessarily if that pushes weight and price too high. Staying under 35 tons should be the objective. Such a tank would be more vulnerable than the Panther, but less than any Pz IV, and no more than a T-34/85. Plus, the Germans might easily have two or 2.5 per each Panther they built.
Manpower may be a problem, but only if the Germans don't gear their armor training schools properly. In fact while manpower was an unsolvable problem of quantity for the Germans when it came to the big numbers, i.e. infantry, that would not be the difficulty with these specialized, highly skilled servicemen. If one has *2.5 tanks, he's better off fielding just a tad less marching rifle fodder and training enough tankers to man the additional machines.
Effects? Well.....