As far as airports go, like everything else in life, there is the good...the bad...and everything in between. And that's where I think PHX falls...in between.
Now, let's start with making connections between terminals, even with airlines who are partners. There is no tram, so you have to take a bus. Always make sure you have plenty of time to go between terminals.
As for the terminals themselves...they definitely are in need of an update. The carpeting, the doorways, the layouts...a bit dated.
This airport just reminders of a smaller scale airport that grew too fast too soon. And for a major hub, it definitely needs to be looked at.
On the other hand, the airport personnel (not airline personnel) are very nice. That's what they have to make up for the facility itself!