I agree. I personally wouldn't have gone for 1upt, instead something more flexible (armies, again), but it is VASTLY superior to SoD combat.
Woops, sorry.
I can only see one thing in the wiki that might work (I didn't check building xml, as if that exists then it's in the schema and easy for you to check). Unfortunately, it has no example, and I'm not sure that it means what it sounds like.
SetCitySizeBoost(iBoost). Also a GetCitySizeType().
I am pretty sure these apply to "Small Medium and Large" city sizes, which are based on population. Each size has its own AI adjustments