I have found that the sump is OK during hard cornering if slightly over filled. This doesn't seem to be a problem. I drive my car quite a bit, and drive it hard. However, if you find a long enough bend, pulling enough Gs... I am sure that there are quite a few guys running sumps with more baffling and someone will have more ideas. The engine has pretty good drain back from the head, and most of the oil stays in the pan. I have not seen any drop in oil pressure when cornering with the sticky 185/70s, and certainly not with the 15" vintage race bias plies. I have done extensive skid pad testing (it does about .9G on really sticky road tires), and never had the pressure drop. But, I understand the worry.
The pan has a baffle already, to keep the oil in the deep part of the pan. Evidently, the braking and acceleration is not enough to unport the pickup. But there are always people who claim to have had a pressure drop. The easiest way to beat this is to run more oil. It's not all in the pan when racing, and wont be hitting the crank and turning into foam. Half a quart should so it.
There is a company here called Sports and Imports(
http://www.sportsandimports.biz/engine.html). They make a sump that has a deeper pickup, and a baffle around it. Very simple, and not too expensive, at around $300 with an exchange pan. They are not showing a picture on their site at the moment. I've see the product, and its pretty simple, and a good deal for the money. This is a lot better than the other baffled race pans running about $1600. It works on the car that has one here.
Any way that you can put the pickup deeper in the pan, and keep the oil around it will improve things.
I would not make the pan deeper, as there is already not enough ground clearance. If you want another quart of capacity, install an oil cooler.
