That's a cute pump, I hadn't heard of one till you mentioned it. Even has 5/16" barbs. At 38 gph it will run out of flow in the higher RPM's. Don't take my word for it, get a gauge on there and see for yourself. With an N/A setup you might not notice it too much, but with a turbo and hotter IP you will likely be under 1psi at WOT.
I really like the return orifice, I also have a filter on the frame rail and added a small fuel manifold in the engine bay just to use that bleeder into the return system for air purging. I have 2 tanks and use them and don't always switch them early enough, so having the air purge is really nice. And yes the very small orifice will keep much more fuel going to the IP than to the return system.
FYI, the 38 gph is mostly for cooling the IP. It's bypasses a ton of fuel!
The easiest way to boost your fuel supply would be to just buy another one, and get some nice "Y" brass barbs and hook them up in parallel. That would double the flow but maintain the correct PSI. And the redundancy of two e-pumps means you'll always have a backup if one fails. Just a thought!
I have a Facet 40222 hooked up in parallel with a stock-style lift pump. The mechanical does a good job keeping up with my setup and the Facet is for priming and starting and a backup. It draws down to 0psi under WOT but it's good enough for a backup.