manyboats, My effort, in part, was to eliminate valves & fittings (especially st.elbows), get rid of all the 50yo copper tubing and gate valves, get the water off the bottom of my tanks where I could drain it, and allow the air (when rolling w/ low tanks) to go back up to the tanks. I did eliminate several dozen fittings and connections, and I think I have given the water and air a path to freedom as it were.
As to filling the bilge with fuel I agree but dip tubes w/o siphon breaks, will put a tank of fuel in the bilge just as easily and mine began to pick up air when the tank was low.
My electric fuel pump calls for a filter ahead of it so that is why I put it between the 30 and a 10 micron Racors.
Please explain where each hose on your existing system goes, I can't seem to understand it and I would like to.