Boris Gudenuf
Deity
This was/is a feature of the game Humankind, and IMHO it's a very good one. It adds to the feeling of a Wonder as Something Special instead of just another tick in a city's Production Queue.What about being able to merge production from different regions to build wonders anywhere they can be built ?
On the other hand, it would make it difficult to build more than one Wonder at once (not a problem in Humankind, which required a massive Up Front cost to get the chance to build a Wonder, so it is generally One Wonder Per Era). Given that a certain percentage of us are Wonder Hogs, that could be off-putting.
All that aside, I'd like to see more Variation in Wonders. Looking at the Wonders in Civ VI alone, they range from entire regions (Ruhr Valley) to entire Cities (Angkor Wat) to individual parts of Buildings ("Big Ben" a single bell in a tower in a government structure). That, to me, cries out for some variation in their placement (as now) but also in the amount of space they take.
Some Wonders should take up an entire tile: The Pyramids, the original multi-acre Stonehenge Complex, Ruhr Valley (maybe even, like some Natural Wonders, Multiple Tiles?) etc. But note that those first two were also not built anywhere near a major residential area/urban area either. Many Wonders, like the museums, art galleries and 'cultural' buildings, Require people to visit for their effect: they have to be built near people, in an Urban setting. But many are also small enough that they should 'fit' inside a single District with Room left over - and possibly add extra Effects because they are, say, adjacent to another Wonder, or the Palace, or Neighborhoods, or whatever.
We could have both more specific requirements to get the maximum effect out of a Wonder, or even to build it in the first place (something I've posted on before) but also greater range of places we can put them. Prime site also has your only Iron resource? there should be other potential sites that don't give quite as good a Bonus, but are still buildable – if you also fulfill other requirements, like having a God King type government to build Pyramids or Terracotta Army