I udnerstand it is important to be out of combat when waypointing to another place. But it is also very annoying when you start to look where your going and something respawns on your back and start attacking you, so you have to close map, kill/run away, open map again, find the right waypoint and re-click.
So my suggestion is to prevent that.
If you select a waypoint while in combat you get an errormessage saying that you are in combat. Do you want to travel here as soon as you are out of combat?
If you answer yes you will automaticly go there when you are out of combat (leaving any loot behind)
Arise, ye farmers of all nations
Arise, opressed of Tyria!