Perhaps include victory conditions, based on "Hates <faction>" traits?

If Kart-Hadast has to be a trade-empire, I assume the relevant settlements get checked for the possession of sufficient trade facilities and mines? A treasury of 50,000 can be gained easily, if military upkeep is low. However, that would not mean Kart-Hadast is an economic powerhouse.

It would be a bit odd that they would conquer the whole of Iberia without developing the rich mines; this of course should be given greater weight for the Barcids.

Other than that, I can't really comment, as I never played them.