Creating Hint Vector

I am more then aware of the two vectors needed in those function, that is indeed why i want to change the axis it is operating on. and as true as it is that you can assign them... its not much more then a rotation, which in this perticular case doesn't help. tho I realize there are many different ways of attack this current problem. if I had a function like Quaternion.AngleAxis that set a group of local rotations... i would also be fine...

So do you want to just do a relative rotation? Something like: You have a local arbitrary direction vector which should point into a certain direction. So you want to rotate the object that this vector (which is fix in local space) should point into / to a certain world space direction / point? If so, why not just using Quaternion.FromToRotation like you've mentioned? It calculates a rotation which rotates a given vector, so it points into the direction of "toDirection"

Example:

 Vector3 localVector = (new Vector3(0,1,1)).normalized; // forward but 45° up
 transform.rotation = Quaternion.FromToRotation(localVector,targetDirection);

I've tested it and it works like you would expect. Of course without a second vector the rotation around the direction vector might look a bit strange, but a single vector doesn't define a whole coordinate system.

without an up vector defined, my ship takes routes that aren't helpful, tho I realized my problem was actually converting a world rotation to a local rotation... and LookRotation was working very well.