Here's something else to try: add a little more expo to your rudder in 3D mode. Awhile back I discovered, by accident, that sometimes I could hover/TR better in normal mode than 3D. What it turned out to be was, I was overcontrolling the rudder and then having to chase it. Once I reduced the effective rudder sesitivity at mid stick, I was able to let things settle down. Once I got confident at these moves it didn't matter, because I could anticipate what was going to happen.

Have you ever noticed how in a nice harrier, when you raise the nose but don't add power the airplane descends, in an elevator? Try entering your hover in the same way. Establish a nice smooth harrier, then pull the nose up. Let the nose begin to smoothly pitch up and then smoothly add power to counter the descent. You'll find yourself in a nice, controlled, stable hover. If you come in with the power too soon, the airplane will begin to climb and you'll have to throttle back to maintain altitude. By waiting a bit, and I mean just enough to let the nose start to come up, you will be carrying a bit of power into that hover, which will give you more control (moving air over surfaces) and make the airplane more stable. With a little practice you can make the whole thing look like its happening in slow motion. When entering your hover from harrier in this way, you'll find there is less flopping around to correct for. Hope this helps!

Dave