I’m a fan of the Smart Lunar R1. Very bright. Has a low mode. Has flashing and constant at same time. And a seat stay mount. And can be had for a tenner.
Can be slightly unreliable in the wet (though it tends to not turn off, rather than not turn on), but only once had problems with mudguards on, and I’ve done some very long, very wet rides.
Also, place yourself in the drivers shoes and ask yourself, if you were following something that was hurting your eyes, would you not try to get past it as soon as possible? Not all drivers overtake safely and those which feel aggrieved/entitled, doubly so.
Where are all these lights that are blinding people? I’m yet to see one. Pretty much on a daily basis however, I see lights that look pathetic and barely fit for purpose. I often wonder if the batteries are going flat or if they’re actually sold like that, but they seem to make up the vast majority of lights on the road. It’s relatively rare I see something quite decent, that really makes a rider stand out from the traffic.