I think everyone is on the money with pickup height being too high. I can't think of anything else internal to the engine that cares much about fore/aft movement with speed changes. And yes running eight quarts would probably get the level up above it, LOL.

When my 360 was leaking like a seive (but the pickup set right) it wouldn't start the oil light blinking during braking trick until about 2 quarts low.

As for the pan being beat up... Many years ago they started the repaving process on a road in my town. Starting with putting manhole risers on which stick up above the road to account for the planned thickness of the new layer of pavement. Guess what, someone forgot to close the road. So I drive down it, see it coming but not in time to stop or dodge it. Put a huge dent in my K frame, then hit the oil pan and put a good inch or so depression in the pan. How it didn't catch the bottom of the transmission I have no idea. Anyway with that big of a dent it never caused oil starvation issues like you describe.

Checking and resetting the height is probably all you need to do for normal driving, although the stock capacity kevko pans are pretty trick. I wouldn't worry about an extra capacity pan unless you have a high volume oil pump and are spinning it way past the redline of a stock engine.