Aside from the issue of too much flow across the fuge, keep in mind that the higher the flow in the sump, the more turbulence there will be. Lots of salt creep and you'll have a problem with microbubbles.

Also, that's an Ocean Motions plumbed in a closed loop on ReefOne's tank. It switches the flow between the pipes. They all don't have water flowing in them at the same time.

No matter how you divert water into your tank, whatever is pumped in from the sump is going back down the calfo. It doesn't matter how it gets in or what it goes through on the way, it's all going back down exactly as fast as it goes in. If you try to limit or slow down what drains back in, it will only go over the top. All that plumbing with so many bends will increase the head pressure and bring down the GPH some.