I don't see any problem with it functioning properly. With your standpipe your tank level will stay high if the pump shuts off.
I would say that the idea here is a good start, but if you use a standard spraybar as an intake, those small holes are going to be very susceptible to becoming clogged. If this happens, you lose your drain and will have a flood. Also, looking at your diagram, it would seem that the suction near the bottom of the "spray intake" would be greater than the suction near the top.