Check your plugs and look up how to read them if you do not already know. I've always had the best luck in these new engines running the AC Delco plug, some of the fancy multi pronged plugs for example make my Vette run like crap.. I gave up ever trying to run less than premium fuel years ago in any of my cars. Yes its more expensive but gas mileage is better too. Also check for how much ethanol is in the fuel. E15 can make anything run like crap. I see you are logging, can you get a TPS reading? That might have an effect.
If all else fails, find a tuner in your area that can take a few degrees of timing out of it. This can be adjusted by throttle position, speed and several other ways so as not to totally kill performance.
Tim