For each of the following. Do you think it’s a buff or nerf?
If:
King’s Palace is moved to Age 2 landmark replacing any of current ones (and maybe production speed is adjusted, e.g. double the time / x50% the speed, or this penalty is even larger). Also with a new age 3 landmark to replace its place.
Chinese/Zhuxi can choose among possible dynasties with a price of resources / long cooldown. For example, I already built IA and Barbican, I can switch between Tang and Song anytime freely/with price above. Similar for 3 and 4 dynasties. The buffs from dynasty can be nerfed accordingly in this case.
Every civ with normal bombard or culverin can choose which one of these two to use. (I personally prefer culverin over bombard for no setup). Techs or buffs only for bombard or culverin can be adjusted accordingly.
Variant of above. All culverins are replaced by bombards. Vise versa.
Every Civ except KT(since no bombard) can now build Ribauldequin.