Try to predict driver behaviour at junctions. You can actually be exuberant in filtering through London’s West End and the City because drivers expect bikes to be there and will look in their mirrors (they know that if they don’t
If you’re in an area where you’re likely to come into conflict with other road users then move at a speed that is not significantly greater than the flow of traffic. The last thing you want is to surprise people.
Fairy lights that modulate at 300-400 flashes per second will be perceived as twinkling. That’s important because the movement draws the eye, increasing your visibility, but it won’t look like it’s flashing.