I don't think you should need a tech or resources to build new Yor. It doesn't make sense to me. The Yor should have been able to make new Yor units in the eons they have existed. They shouldn't need new tech. Likewise, the resources needed to build new Yor don't exist on the Yor homeworld. How could have they survived without such resources?
Edit: An idea I have, I think it would make sense for The Yor to start with the ability to produce Yor, but for the process to be a bit different. It would cost more production, but it wouldn't require fancy techs or special resources.
I disagree wholeheartedly. Carbon species (and I suppose silicon ones, though this is yet to be proven) grow naturally. It is just a function of their species. Yor already have Extreme Colonization (which is far better and more interesting than in GC3, so far). Unbounded ability to grow would make them extremely overpowered.
In playing as Yor in the recent Alpha, the search for Promethium has been a huge impetus in my expansion (Durantum seems to be more common). This gives me a reason to research travel through the gates.
(edit) also, the need for the two resources is not all that great. Survey ships can reward both resources. Between that and a few constructors (or planetary mines) the resource requirement isn't very limiting.
