Moving to the left has been the single most effective instant-change-creator for me, too. This is somehwhat true here, but even more on a busier-than-I-liked 100 mile rdie with a friend. It was simply amazing that when I went out a single foot - about where the right tire of a car would be - drivers passed with more room. (They were still going fast, but further away.)
Another idea is to get one of those 'flash flags' ... another link here . The flag sticks out but is flexible so if you hit something it just bends, but it draws attention to your outside self.