I think the balance of a single engine is a catch 22. Obviously the rear of a twin is heavier, but the torque steer you get with a single can make the boat land on its side when it launches and will have a tendency to not run level. You will alway be messing with the tabs just to get it to drive level. In a twin, your just pointing the nose up or down. In a single your doing the same, but your also trying to get it level.
Were is that kryptonite video mastercraft posted. Watch when it launches the boat dipped to the starboard or port (can't remember) he didn't come down flat. I have had numerous bad landings trying to manage the torque steer of my old 24 python, which is why I sold it. The twin engine boat I have now is 5 times easier to drive, granted it doesn't have a pad bottom like the 24, but it was the torque steer that drove me nuts. Why do you think mercury made a special NXT drive just for single engine boats?