That last line was meant to be Vidanta, I have corrected it in the original post. We don't want AI, so I think any of these would work. Is the extra cost at the Vidanta resorts worth it? Some of the reviews said they didn't like how isolated the resorts are and how long it takes to get to your car.
Ah, OK.
So, I've not stayed at your first 3. I have stayed at Vidanta. If you can get into Grand Bliss or higher, IMO, the accommodations are much nicer (again, I've only based this on pictures of the others). Yes, the Vidanta isn't "close" to the action like the hotel zone is, but you stated specifically to visit ruins, Xel-ha, and Xplor, in which case, it's the closest of the 4 resorts. I'd say that you'd be looking at 1 hour travel time just to get from the hotel zone down to Vidanta's location, depending on traffic.
Although with the addition of the Jungala water park, and the Cirque du Soleil, it helps not feel as isolated.
IMO, the Vidanta resort is about "mid-way" (not quite, more like 40 minutes south of the airport and 20 minutes north of Playa, again depending on traffic) that you can take a taxi (or drive if you prefer, but that's not my cup of tea) to Playa or go up to Cancun.
But the 3 things you listed are all considerably south of Cancun (and thus "closer" to vidanta).
Now, is it worth the extra $6whatever that Vidanta charges by RCI/II access? I'm used to my $75 SFX fee, so I say "no". But if all I have was II/RCI, then I'd try most definitely to get Grand Luxxe. However, as an exchanger, the Riviera Maya location won't let you have access to the Beach Club, the Grand Luxxe pool, nor the Burger Custom Made (restaurant by Grand Luxxe Pool). So that sours it for me as well (even SFX gets restricted).
Nuevo Vallarta doesn't have the restrictions currently.
Hopefully others can chime into the other locations.
Note that I would have no problem staying at the Westin, if I was just wanting to be on the beach and stay up in Cancun.
Hope this helps somewhat.