I love Paley park. It's very subtle, nothing presumptuous, but beautiful.
I also like Eliasson a good deal. Saw his current exposition at MoMA, and liked it well enough, though I wasn't exactly swept off my feet. Guess I'd have to see the waterfalls first to know if i like them, but i wouldn't go out of my way to go see them, so i'll likely never know and that's fine by me.
I like this piece (Remagine) especially, though this wasn't at MoMA: