I had to ask one of the riders with our group, on a MUP during the day, to angle his light down as it was blindingly bright. I use a small light, just to be seen in the shadows when riding, but it's not high powered (understatement). I've noticed the cyclists coming the other way are much easier to notice them approaching from shadowed areas. Most don't have super-bright lights (or maybe have them on low and angled downward).