Look at one of the carb cycling diets. I tried one by Lyle McDonald that gave good results. They usually have a clear workout routine with them that are designed to break through plateaus. Body building is an art and a science. You may want to explore specific programs designed to get the results you want. There are plenty on the forums here. When you find one you want to try, I would recommend creating a workout journal. It's just another way to focus your training, and get the most out of it. Kudos on your accomplishments so far. If you were able to get this far, you can definitely achieve all your goals.