Because you don't like fighting against certain unit is not a reason to nerf it.
First of all, there’s no comparison between the Luchs and the T70. None.
Second, you pick mobile defense for the Puma, so you should have it available for its intended role, aka stopping the T70 from winning the game on its own. As OKW you can get a fast Puma and do that, but Ostheer is stuck wih an arbitrary 5CP requirement, hence why I suggested a small fuel cost to unlock the Puma earlier.
There is no justification to letting a unit roam without a counter and wreck a game. None.