Fish farms and hatcheries use paddlewheel because THEY WORK, plus they are efficient. They circulate oxygenated water deeper than the top 2-3 feet, my best guess down to 6-8 feet. If you have a good paddlewheel, and run it 24/7 during growing season, then you will likely be saved from a fish kill even if your pond or lake suffers from turn-over or plankton crash. However, the diffused air systems won't do squat for you during an emergency. Your pond can suffer oxygen depletion regardless of fish capacity. My advise is for Tracy, based on experience. A 2 HP should be enough to handle the 3 acres, as long as you continue to run the diffused air also.
