It is an additional purchase, but the Curve Editor provides what you need, if I understand you correctly.
If you have separate XYZ keys in the timeline it would be hard to know which ones are superfluous. All data is expressed in world space, so if a character or something else is turned other axis values, than the obvious one may change as well.
In the Curve Editor you can really see what is going on, and it has an option to reduce the number of keys.
EDIT: I notice this is posted in the CC wish list, but this would really relate to iClone as CC doesn't deal directly with motions although it can export them.