Just observations:
Oil pump upgrades generally produce enough pressure (with your chosen viscosity) to keep all parts wet, cool & safe during whatever the engine does. For most engines, the usual "10 psi per 1,000 RPM" is enough (at the gauge, the actual bearings see much more), and this can be obtained (in many engines) by lighter oil than you suppose. More than that just beats up the pump drive, and may de-stabilize the linked ignition timing.
Regardless of pump size, when the relief valve opens (* most of) the extra pressure and volume are short-circuited to the pump inlet or the pan. The engine can't get any more than the relief valve permits.
* with OEM and some other pumps, the relief valve will not pass the entire over-pressure volume, causing system (line) pressure to spike and blow out cam plugs, seals etc.
