I would like to know what he's eating (grain, hay, supplements) and how much turnout/pasture time he gets. Food and turnout time both greatly effect a horse's energy level and behavior.
If he doesn't get any (or much) feed or grain, little to no Alfalfa hay, and has at least 12 hours of turnout time, then I'd suggest getting some Dressage lessons on him before changing bits. You may just need to learn how to more effectively communicate with him, to help him understand what you want better (slower gaits). Learn to use lighter leg aids, more seat aids, and softer/quieter hands/arms/shoulders to give him a sense of "calm" in the saddle and slow him down with little to no rein pressure.