Telling the Editor to do something by shouting at it.
Making the Editor write love poems.
You might notice the sarcasm in my words :0
1), 2) and 3) are possible by editing the model itself. The Flashlight is an integral part of the model, I also can't just chop off a dude's arm in the editor. And player colors are just not on the model - if they're not existent then you can't use it. Custom portraits can be created (hence custom), you just need to add a model camera to the model and you should be able to use it as a portrait.
A list of impossible things would be as long as human imagination lasts. The GE just isn't omnipotent. Just when I think about what the editor can't do I get overwhelmed by the sheer amount of things that come to my mind.