You can relax the limb a frame or two before the impact in order to slightly dampen the momentum if needed.
Also, experiment with different gravities, -15 and -9 manips can look sweet.

Also also, avoid grabbing until AFTER the first hit, looks sloppy if you have to grab during the manip, or to get the first hit.
It makes it look like you need to grab in order to get Uke where you need him, instead of being able to do it naturally.
Larfen taught me that and he's the manip god. Hands down.