Hi,
Being able to display the motion trail of various controllers (or objects) will be a great addition to Iclone.
This simple feature helps tremendously to clean mocap or track the arcs on keyframed animation.
I personally use this for ages on various projects like Assassin's creed Valhalla (mocap and keyframe in 3D max and MotionBuilder) or Guardians of the Galaxy (mocap with MotionBuilder)
On the image you can see the version of the motion trail in UE5