it might be a good option to mount the ESC's behind each fan. since you aren't pushing a lot of power on 4S or 5S, you shouldn't be worried about wire length. on 4S, I ran a wire 22 inches from the battery to the ESC connector. the battery was slightly warmer than when it was the stock length, but not by much. ideally, you want the motor to ESC wires a bit longer, but at these power levels, it's not a big deal which wires you extend. if it were me, I'de mount the ESC's behind each fan and run the wires up into the wings. mount the packs in the wings if there's enough room, or further on into the wing root somewhere. just a thought.