It more or less is wonders from Civ already. Especially due to placement restrictions in Civ 6. The only difference between the two is that Civ 6 maps are randomly generated, but for some wonders the areas you can place them are limited to few enough places on the map that only a small fraction of the civs can a) make them and b) get useful benefits from doing so. Others are more like previous games in that they don't have high restrictions.Both good points. Monuments don't necessarilly need to be fixed in every case, but there should be some restrictions. Otherwise this basically just turns into wonders from Civilization.
Something like 15% admin efficiency is wild and making those kinds of bonuses arbitrarily constrained to a few spots "because that's where they were made historically" doesn't make sense. Especially if the country that made it IRL doesn't even exist on the EU 4 map in question.