Hello Umberto,
First off, I want to thank you for being so receptive to suggestions. As a user, I really appreciate the fact that you listen to us. The last one I had was the fuel truck, but you beat me to it and were almost finished with it before I suggested it. You did a fantastic job with that, btw.
Whenever I get assigned to a gate where the marshaller is inside of the building, I edit the position to set the distance for him. In most cases, I have to guess the distance then exit the editor and then request parking services again to have him get redrawn in the new position. If I didn't get the distance correct, I have to re-edit and try again. It can be quite tricky to get him into a correct position sometimes.
My suggestion is to either put a mark on the ground in the editor where the marshaller's current position is (possibly with the actual distance shown next to it), or to put some sort of line with hash marks and distance numbers on the ground so we could tell what number to input into the distance field. That way we could see in the editor where he is standing, and see our changes immediately without exiting the editor.
Thank you for considering it.