Well, I can attempt to help, but I'm not an expert on this at all. From what I've read, I don't think you should need that many 703s, specifically on the side and front wall. Personally, I would probably put one on each wall: directly behind the mix position, directly in front, and on the left and right walls, halfway between the mix position and the monitors. Also, one on the ceiling, halfway between the mix position and the monitors. I'm not sure about the one you have in the corner of the ceiling behind the monitors, that would operate as a good bass trap, I guess, but you need something right on the ceiling between you and the monitor to cut out the early reflections, so I would move it there from where you have it.
Then, if those foam things are good bass traps, I would put them in EVERY top tri-corner. Personally, because I know they're good, I would go with ethan's realtraps, he makes 2x2 minitraps specifically for those tri-corners. Depending on how much room you have, I would try to put a larger bass trap in every corner I could, but failing that, I would mount them flush to the wall, starting with the back wall/front wall.
Just my two cents, take it for what it's worth.