The psu is fan down. It sucks air in from underneath, doesn't blow it out. It blows out the back. It's basically self contained and doesn't affect temps or airflow inside the case.
Both top fans should be mounted as exhaust. Doesn't really matter much if they are mounted underneath the rad (push) or above the rad (pull), as long as the airflow path is set for out not in. There are distinct advantages to pull though, which is how they are physically mounted in your picture. Pull gets lower temps at lower rpm than push, so if you run silent mode in Cam your fans will stay under @ 900rpm, and is more effective. It's only when fans spin over @ 1300rpm that push is more effective.
The other advantage is cleaning. Far easier to clean the dust out of the rad, since it's visible, you don't have to remove the fans to get at it.
The front fans should be set for intake. Whether you use a rear exhaust is up to you, in my case (kraken x61) I actually raised cpu temps with a rear exhaust mounted as the top rear fan of the radiator lost airflow. It got stolen by the rear exhaust.
With a set in-front-out-top pathway you maximize airflow in a direct line, additional fans just confuse that, adding irregular paths.
Oh, and personally I'd see what could be done to turn your pump head 90° to the right. Not only will that set nzxt as horizontal instead of vertical, but removes the usb/wiring from sticking directly into the ram...