Rotating without the curves

Is there a way to rotate an object in the animation manually without using the curve system, as it does not look very good when it spins around and does loopty loops.

Sure, there's a couple of ways to rotate objects from scripts and you can also trigger scripts from animations. Some links to the API reference (you'll use the Transform component attached to the GameObject for this):

If you are working with physics and Rigidbodies, this may also be of interest:

For information how to add animation events to your animations (i.e. hook scripting into the animations), see: