It's frustrating to try different things and not get results--I remember! Salicylic acid is great stuff! With diet, it sounds like you're doing great by just gradually switching over to healthier items, like adding in the whole grains.
Leafy greens are the most important skin food to get in. Even if you don't change your diet much, if you can just add in one green smoothie a day (link in my signature below explains), you might start to notice changes, because this will add major nutrition to your diet. And hang in there, sometimes it can actually take months before diet has an effect. I believe it often takes years for the body to get to a state of imbalance, so we can't always get the overnight fix we want with healthful changes, as it takes time to undue all the years of bad food, toxins, etc.
Definitely avoid hydrogenated oils when you can (often in processed foods, which should be limited also). High-fructose corn syrup is another to avoid when it's under your control. I agree that you still have to live your life, and you can't avoid these things 100% of the time.
Also, you might want to try a product called Cataplex E by Standard Process. One of my chiropractors says this usually works on all of his acne prone patients. This is his top recommendation, and he knows his stuff better than just about any holistic doctor I've ever been too.
Regardless, it's looking like you're on your way to healthier skin! And a good side-effect is that this is making you more aware of living a healthful lifestyle, which will definitely help you down the road!