Sky Harbor is an okay airport. It's pretty dated (think one phone charging station per terminal, rather than multiple plugs all over the place), but it gets the job done.
The staff is friendly and the security lines go quite fast. There is also ample seating at each of the gates, which is something I have seen to be a problem at other airports. There is a fairly decent selection of food and shops and the bathrooms are large and clean.
The baggage claim area is a little bit cramped and the carousels themselves are pretty dang small so bags get piled up quickly. The entire airport is a really expansive place and it takes a lot of time to walk from place to place. These are minor cons, but no big deal overall.
However, the one major con to me is the crossover from the baggage claim to the rental cars. You have to go outside and cross the street to get to the rental car shuttle area. On both arrival and departure, cars were racing through this area and it felt pretty unsafe for crossing pedestrians. I'm also not a huge fan of having to take a shuttle to the rental car complex in the first place, but I guess that is more of a personal preference.
Overall this is a fine airport, nothing special.