Phoenix is the most efficient large size airport I've been to. Security moves pretty quickly. It can be overwhelming with all the different terminals. I fly southwest mainly so I just remember that southwest is Terminal 4. There are plenty of restaurants (good ones) to choose from. My favorite coffee stop is the Peets Coffee right after security at D gates, simply because the drinks are delicious and there are plenty of lounge chairs and charging ports. There are a lack of charging ports in the D gates which is a downside for me. Also the other thing to remember is if you are renting a car, the shuttle ride to the rental car center is about 10 minutes so be prepared early so you have a little bit more extra time. With water bottle refilling stations and good eats, I don't mind layovers at Sky Harbor at all!