I usually ride in a bright long-sleeved race top (Giro Pink or TdF Yellow) with 2 rear and 2 front lights.
I usually switch on only one light each end; the other is a spare or for rain/mist etc when I'll use everything I have.
My helmet (when I wear it) is a light, bright colour. I sometimes wear a hi-vis gilet (but normally for the cold, not visibility...)
I base my after-dark precautions on what I see working or not working on other cyclists when I'm driving.
I do think vi-vis is a good thing (like other posters).
I drive past many, many cyclists with one front and one rear light who are almost invisible but clearly think otherwise.
Dark clothing just seems to suck away the visibility of even a modestly illuminated rider. I have no idea why.
Be very visible. Be as visible as you can be. You'll never know how many times it has done you a favour.
My only caveat here is that I wouldn't put front lights on flash mode.. as a driver I find myself distracted and iriitated by that and it's often right at driver's-eye level. I'll put my rear/s on flash, but never my front/s.