Personally i would recommend to rename some of the national wonders to make them less civ specific (of course you dont nees to do this). Here are all of them:
Mount Rushmore -> Historical Monument
Wall Street -> Stock exchange (If the english has the same UB, rename it to Bank of England)
Oxford University -> National Science University (or something like that)
That's all.
PS
Also i would recommend this (beneath) as a world wonder of some kind
Svalbard Global Seed Vault
I also have a Quote for this (if you want to have quote with it):
"This place is abondoned by God and ought to have been abondoned by mankind as well" - Unknown person about Svalbard
Nice! This could be one of the future Wonders that we were looking for (I know that it is already completed but we really need some future wonders ).