Great suggestions (some of them seem a little... familiar ). I too would love to see more modern variety. Korea is a great candidate, as you said, for a fantastic late-era UB. PC Rooms litter that country- could be a great +Happy, +Science building (Maybe -population growth for realism ). Maybe the Hakka gets replaced by an Ikea-esque UB? Maybe something that boosts late game trade routes (once BNW drops, of course) or boosts hammers.