I agree, this would be very useful. The tracking station already has two buttons, one for terminating a flight and one for continuing it. It could have a new button for renaming and reclassifying the selected vessel.
When I'm trying to do a gravity assist using Mun I can see my current orbit (blue) and the one (yellow) that will be when I captured by Mun. But I want to see what kind of orbit will I have after the rocket laves Mun. Before entering Mun's sphere of influence of course. Either a mod or settings file editing would do for me.