Hey there! I love Vegas, been there several times! I'm no expert on the city but If you have any questions let me know!
I wrote a post about it here https://steemit.com/travel/@jed78/hello-steemit-going-to-vegas-here-are-some-travel-tips-and-places-to-see
Hope you have a great time! As for the proposal, check out the gondolas at the Venetian Hotel, or in front of the Bellagio fountains!