Panther itself would probably also need a fuel cost reduction, but it'd certainly fix how much sooner it arrives over the Wehrmacht's is definitely silly, even considering the Wehrmacht's overly-high teching costs.
Honestly just removing Obers and putting the PIV Ausf J (which costs 105 on it's own btw) on the Schwer would be cool. Make the KT a late game unit like it still is with all the converted HQ's (but limit it to only 1 or something/make it give a fuel income reduc), and make the Elite Armored give you Ausf J aces with a high cost like the Tiger Ace that reduces your income.
Makes everyone happy, no more Obers, an actual medium tank people can use instead of just waiting for Panthers, KT is limited, and Elite Armored no longer blows ass!