I had a very minor league and very short MMA career (3 years), and I worked as a personal trainer for six.
What I would tell you is this. Being as that you are only 14, focus mostly on carido. Run, swim, and bike as much as you can. Don't stop lifting weights, but stay away from power lifting until you are at least 16. Stick to low weight high reps, it's better for you in every aspect of physical health, and in the fight game.
As far as getting into MMA. At 5'11, and 215 you're on you are most likely going to become larger in stature over the next few years. If you were that large at one point, chances are you're going to develope into a Pahlharres (spelling
) type of build... as young as you are, and at that height. My advice would be this... strive to lose more weight and target the 170 pould weight class... as you get older you'll probably be forced into the 185 class simply based on body mass.
Now, I say all this without seeing you, and knowing a propper body mass index, but my guess is, at that age you've probably still got a lot of body fat you can lose and turn into lean muscle.
That's the best I got for you for now. Good luck, and stay on this forum. This is a rare forum that isn't just built on keyboard warriors... people around here know what they are talking about.