Forget what the RPI numbers are for a minute. IF Arizona had played those teams as you suggest then yes I would be less inclined to find them worthy of a #1 seed. A team should be judged on the body of their work and when it includes teams such as those noted then it takes away from the rest of the work.
I also don't agree with the idea of "did you do what you were suppose to do" against an opponent. This becomes extremely subjective and now were closing in to BCS type rankings.
The RPI is not a good measuring stick. Replace it with the ISR formula.
Arguing that the RPI is not a good measuring stick is a completly different issue from scheduling appropriately using the RPI. Which means as long as the RPI is going to be used we need to change a few things.