Personally I could quite happily have an Ostheer without Panthers, Tigers and Panzer IV's, make some room for things we havn't seen before n that.
But I think buildable Tigers would be an ok idea, provided they were weaker/slower than the Wehr one, and had a unit cap.
Call them "Tiger Ausf. H" or something to signify them as early war tigers, compared to the "Ausf. E" late war ones for the Wehr. Or something.