I love Gatorade and drink it both during and post workout. I like it because it gives me a good deal of potassium and decent recovery. But I want to take it one step further - what is the best supplement that I can mix in with my Gatorade bottle?

I'm not very sophisticated with my supplements, I only take creatine and have a protein shake every once in a while (prefer to get my protein from meats). So, what powders/products should I be looking at that would mix well with my drink? A whey protein powder? Something else?