in the display rollout there are options for display proxies. plane pyramid, box, thin box and plant.
the issue i have with all of these is that they are all symmetrical, so i can't tell the direction it's rotated.
i use forest to place large amount of houses and i need to know if the front of the house is facing the street.
i also use it to place large amounts of cars in parking lots and i need to now if the cars are pulled in correctly.
i would like to suggest viewport proxy options of a triangle and an axis