Something a little more convenient, like a single button? There are times when you get aggro and mobs are all over you, so you'll want to kite and dodge around while trying to leave group. A little irritating to have to do the right-click and select from menu.
Something like a EJECT level on a fighter jet if you will.
Maybe just have the group leader /kick you then. That way you don't have to do anything.
Better yet.. don't get agro.. it belongs to the tank.