You don't need a trans cooler.
You may or may not need an oil cooler.
Search on here for ARC cool fins and try that first. Looks jerry-rigged, but does actually work. It's under the car, is inexpensive and JDM (bonus!)-- if it works and you need to drop oil temps closer to water temps, give it a try.
Anyway, If you aren't hitting 250+ F* in normal driving, and aren't tracking the car, leave it be.
Also, if you are new and learning about mods, dynos, etc, search for my Proven Power dyno thread. Lots, and lots, and lots of detail, dyno graphs, commentary on the effects of various modifications, interpretation of dynamomemter output, etc.
IMHO, a good read. I'm long winded, so bring a few beers to keep you focused
