From my experience its always the least civilized factions that exhaust their build list quickest. Notably Sweboz and Lusotannan... But then they have so many restrictions on their actual financial behaviour it does seem consistent. And you can always just waste your money on a fleet if thats the issue... What would be truly impressive however is if you could somehow limit the growth of cities more. ie -3% growth on lvl2 government, -6% lvl3 and -9% lvl4. This wouldnt represent "real world" population, just the limited effect of a disenfranchised population's influence.

Add in a few 60 turn build items for level 1 (and 2?) aimed at expanding the importance of the homeland, then this fan at least will be over the moon!