Very nice changes.
My only concern is the call-in tanks. With such heavy costs of teching, is there any reason not to go T1-T2 -> Tiger / IS-2 / T34/85s?
For example, with the new teching costs it will be more expensive to call in a single T34/76 than it is to call in a tiger.
We will have to wait and try out the new patch but you have a point. Least this may see some valuable changes to T3 units later on if they are going to be that much more expensive to reach.