Aside from the fact that there's no head in that diagram?
The "Y" valve set for the bilge emergency pumpout might be a problem since you are forcing everything to go "up and down" the Y during normal use, and that's more prone to clogging than a straight pipe run. If you rotate the "Y" 90d ccw from the way it is shown, the Gusher can suck either source through a straighter passage. Or, eliminate the second "Y" and just decide that in a real emergency, you're going to cut the hose and use it as a bilge suction line. (Or maybe install a straight fitting to open up. The purpose, again, is to have a smoother run for less chance of a clog, and one less valve that can fail.)