I'm not ready to make a judgment on you're exact situation just yet, But I've experienced the scenario you described before.
It was from hard on the brakes with a short shutdown area that thru what oil was in the pan forward, and away from the pickup.
You may not need more capacity, but I found that a properly baffled pan can make a big difference in that situation.
my oil pressure goes from 65 to 30 after 1/4 mile pass 3 years no prob. 65 all the time now it jumps after a run then goes back to 65 on return road open to ideas