Both are good options, IMO Vdara rooms are much nicer than NoMad but I've only been to NoMad rooms once. Vdara rooms have full kitchens in them - even the base rooms - if that matters to you. Personally I love being able to stash a few Gatorades (or whatever) without worrying about it.

Its a very easy walk to get to Aria or Cosmo - or Bellagio when the walk way reopens this summer.

As far as transportation goes - its very easy at Vdara, ridesharep pickup is right out front of the hotel and they can be on the backroads or highway very easily.

Honestly they are pretty much right next to each other so as far as being "closer" to where you are going, Vdara might be barely, barely closer.