I'm pretty sure that by default SP immigration is added to EA immigration and that the immigration gauge must be changed to override EA immigration. I've never tried it though, because there are too many supernaturals and especially werewolves in my bin, and the whole town would be hairy and howling in no time if I tried SP immigration LOL ! I hope that you find how to let new sims immigrate, I agree pudding faces are boring. Personally, I randomize them all in CAS until they look decent but it requires so much patience.