Thanks guys for your very positive feedback and comments, cheers! 
@ suyati: thanks ! All crucial work is handled by custom nodes, no maya IK, no maya IK Spline Solver, no maya constraints. But I can constraint maya joints directly to the handles to drive some deformation skeleton. The speed depends on the number of handles, but on a normal character it is about 20-25 fps on my macbook pro.
@tonytouch: thanks! question1: See above. question2: yes, anywhere. You can also attach the elbow to any other handle. There are no predetermined ways on what is allowed to be attached where. If you need to attach the elbow to the left ear, no probem.
@Mydrako: thanks! Something like a prop should get a handle and thus have all the possibilities any other handle has, so you can drive the prop with some limb or use some limb to drive a prop. The remote control of the monkey got a handle and then I could just animate the space switching between the crane, falling free and then being caught by the monkey.
I really appreciate your great feedback, I love u all! :love: