You are quite correct, it is definitely not anything related to P. maricopa, the spines alone rule that group out. I would have to say based on your information we are looking at P. barbatus. When I looked at your pics I did not see the spines. P. barbatus is quite wide spread and I think would certainly be in your neck of the woods. I am not sure about species from the californicus group.
You are quite correct the keys are kind of tough I would suggest you look for a copy of the "Ants of Deep Canyon" or "The Ants of Nevada" By George and Jeanette Wheeler, although not for your area, they have good figures which will be helpful and a good glossary as well.