I'd make them all compulsory/law. The only issue is the one about taking the middle of the road. That one is a bit misleading because cyclists are taught to 'take primary' anyway at certain times(pinchpoints etc).
Helmets is a no-brainer, hi-vis too. I'm always amazed at the amount of cyclists who wear dark clothing, with a dark helmet on a dark coloured bike!
Lights, I have one constant and one flashing at the rear(both on the seat stem) AND front(constant on the handlebars, flasher underneath on stem), as well as a flashing one on the rear of my helmet. As far as I can recall, a rear constant is required by law anyway, I add a flasher for extra safety, along with my helmet cam.
I basically look as bright and garish as possible and my bike is lit like a Christmas tree.
My ethos is: If I get knocked off by a motorist they're going to have to explain to the magistrate/judge how they missed seeing me!