Mesa and Barringer for me. Mesa is more like "Meh"sa, but hey, it's an unimproved Germ hill that doubles as a mountain tile for an observatory.
If the NW's position is good, I will pretty much go for it. Near river, hills, a lux or even two.
And we all know the initial thought when you find a natural wonder early on. It's "Dang, why didn't I choose Spain?"
But it does grind my gears when Krakatoa appears, because 8.7563 times out of 10, it's useless. The yield isn't anything to write home about either. A measly 5 science. Yet another case of there needing to be either a lot of fish, atolls or possibly a lux around it to be worth settling near.