As far as major American airports go, Phoenix Sky Harbor (PSH) is an amazing place. Clean, modern, well maintained and easily accessible.
I often fly through PSH because of my love affair with the 'heart' airline a/k/a Southwest. It's one of SW's hubs and for good reason. With the beautiful Arizona weather and large, modern airport it makes for a great option.
There is, of course, some walking to be done as with any huge airport in a major city. However, PSH accommodates the lazy with moving walkways. Yes, I admit I'm the guy power walking on the left side. Makes you feel like a fast forward cartoon!
Despite the size of the facility it's immaculate when compared so some of the aging monoliths in other cities. You won't find disgusting carpets or worn out chairs. Everything feels modern and clean for such a high traffic airport. Even the restrooms are spotless and taken care of.
One of my favorite features on PSH is the abundance of charging station for travelers with hungry electronic toys. Nothing more annoying that having your phone at 3% with no plugs in sight. That's never and issue at PSH.
Overall, PSH is a great airport. One of my favorites.