Higher pressure = less contact patch.
Lower pressure = more contact patch.
Basically, you want to run the lowest tire pressure that doesn't sacrifice something somewhere else, because all else being equal, more contact patch is better.
Side note: Sometimes somebody goes back to a simplified version of high school physics and says that contact patch size shouldn't matter, because by that simplified model, the amount of force required to slide a mass across another mass depends only on the coefficient of friction, and does not depend on the size of the contact patch. That's true to a first level approximation in ideal lab conditions, but doesn't hold up to the real world, where you're driving across rough asphalt using a tire which is not only grooved, but which flexes before it breaks loose, and because it flexes, it's possible for parts of the tire to break loose while others have traction. Ever hear a tire squeal while it doesn't break loose? That's part of the contact patch breaking traction while the rest of the contact patch grips.
Sidewall deformation is something to be watched, but it's not something that you need to stay away from at all costs. This is me driving the car I drove at 2006 SCCA Solo Nationals in a Street Tire class (STU):
Look at the sidewall deformation on that front tire -- it's not pretty. But we had contact patch, and the suspension to keep that contact patch in touch with the ground. After Day 1 of the championships, I was in 4th place out of 48 cars, and the fastest Lancer Evo in the class. (I had cone trouble on day two, but that wasn't the tires' fault, that was mine, for thinking that I was in striking distance of a class win, and over-driving...)
If we had pumped those front tires up to 38 psi, we probably would have straightened that sidewall out quite a bit, but we would have been slower.
If you stay away from rollover at all costs, you may never figure out how fast the car can be. Experiment. I've run as low as 26 PSI at PCA SDR AX events in the last year, and as high as 42 PSI. (Years ago, I took a set of Toyo Proxes RA-1 tires up to 55 psi at an AX event. It wasn't great for traction, but I did learn something from it.)