Natural Wonder
As I'm working on adding this feature I'm also thinking what the best approach would be?
One thing that I'm mostly certain is the

generation:
All of them will give +3

(general)
Natural Wonders may inspire religious or scientific thinking, one may get a profitable idea, create a great art, stumble upon an engineering solution or something else...
But other than that how to proceed?
Actually I already have collected my ideas about which should do what but I'm still looking for improvement if possible.
Platyping's original modcomp: each Natural Wonder has a different, unique effect. Some give local bonus, others have civ wide effects. They are rather unbalanced against each other.
Civ5: Natural Wonders mainly give just a big yield bonus. Each different. Permanent empire-wide

Happiness boost when discovered.
Civ6: Similar to Civ5. Xp bonus for Recon units when discovered.
Civ7: Similar to Civ5/6. Bonus gold when discovered.
Humankind: similar to Civ5-7 with some civ wide effect. A common thing is that all of them has "
+10 Stability on City or Outpost" effect. Provides a one time science and fame bonus when discovered.
Millennia: provides rather a one time bonus when discovering and passively generate

Culture.
I'm also thinking about attaching a resource bonus to the Natural Wonders, so some buildings (Tavern, Hotel, etc.) and some corporations (Safari Hunters, Mile High Travel, WisDome, etc.) could benefit from them.
But should it be Tourist Site or a new resource? Actually I'm leaning toward choosing Tourist Site and slightly decreasing its probability at map generation.