Oil cooling is really sort of over thought most times.
Questions needing to be answered before you go cooler are quite simple.
How warm does your oil run as it is set up now?
At what running condition does get hottest?
How often do you run it that hard?
How much and what type of oil?
What do you have for windage control (many times it's foam causing the excess heat)?
How is your cooling system set up?
GT