The thing is bikes, almost regardless of size, at one time or another are invisible to cagers. Not particularly because they are exceptionally careless but because of the "gorilla in the room" phenomena (). It's been proven the brain can only register so much info at one time, picking and choosing what it sees as the most important. Unfortunately, because most cagers have little real experience with bikes they become invisible. It sounds like you did every reasonable thing to avoid being the "Gorilla", but all circumstances can't be controlled. Pipes can be that one more safety device to keep the rubber on the road. Which brings to mind the Elio. The pure novelty will give it added visibility, but there are other additions to it that might be made if we are concerned about its visibility in traffic. Extra lights, louder horns, reflective strips for night driving, bright colors. Regardless of all that, the best tool for safety is to be alert and like a WWII fighter pilot, keep your head on a swivel.
Novelty catches people's attention. When the 3rd, center-mounted brake light first appeared in road tests, nearly EVERYONE noticed it with a high recognition rate, and the government mandated it. A few years later, the insurance institute assessed rear-end wreck data and found virtually zero benefit from having a 3rd brake light. Yet, the 3rd brake light is still mandated, despite having no gain whatsoever for safety.