Hmm. I'm not sure its much of an improvement to be honest. At the end of the day, it's something that's virtually impossible to protray realistically. I remember trying on my watchtower map, which was unsatisfying if I recall. I recommend you just keep it simple, it probably doesn't really matter which way is up or down, people will be able to work it out, and don't worry about it too much. Perfect something that's actually perfectable.