I have a cheap (because a new one had come out) cateye on the bars. It isn't quite bright enough to see sticks and holes in dark lanes at 20km/h, but scatters wide enough to get me seen and balances well with my helmet mounted Fenix. I use that on low-ish beam in town: i don't need it to see by and flashing it up at a car has always got me noticed so far. On lanes I go to a brighter setting. I've yet to have the luxury of night vision unspoiled by car lights (astronomy experience tells me that takes 20 minutes to fully develop). My rides have very mixed road lighting and speeds so easy changes in brightness and how far ahead I point (but always down unless mimicing a flashing car headlight) were part of my plan.
On the back I have two pretty cheap lights, for redundancy and because I think two lights are more noticeable than one bigger light. I'd have another light on the front if I could fit it on the bars.
I don't use flashing lights as I find it hard to judge speed and distance so well with them, so I assume others do too.
To that I add a hi-viz / scotchlight vest, ankle bands and wrist bands, which helps on the being seen front. The ankle bands do roughly what a flashing light does, I think.
