Thanks for the replies
Yellowstone may be a very good option
Another option we were discussing was a Disney Cruise, so let's see which one we take this summer
And no, Asia is no way possible with my 3, by then 4 year old. He was able to handle the ELP-SAN (no longer available via WN

), but the ELP-ATL-MCO was barely manageable. Anything longer than that, and I am afraid we would be kicked off the plane, mid flight.