I have seen some serious arguments regarding fuel systems, the math, if you can use it properly is the best way to calculate system needs. My theory is to throw more fuel than you should ever need and use good regulators to control its delivery.
My current set up is capable of supporting around a 200 shot in regards to fuel delivery available. It consists of a 10 gal. fuel cell, -8 to a blue pump, -8 from the pump to the engine bay (avoiding any tight turns or changes in direction when possible). Then it splits feeding two Holley 4.5 to 9psi regulators -8 in, -6 out to the carb and NOS fuel solenoids with a return on the fuel solenoid regulator to avoid dead head pressure.
Once I set the power levels (jetting) I can tweak (lean or richen) the mixture with regulator pressure providing I have a workable air fuel to start with. It's worked well for me so far though I'm sure there will be those that disagree.
Sounds like you have a good idea with the two pumps, as long as you don't short-cut things. I got to go for now so I'll try to get back to you tomorrow when I have more time.