I see you have already realized 15 lumens isn't gonna work. I used to have a 40 lumen light when I started cycling. I thought it was good because most people would see me at dusk. When I had to get home after the blue hour a few times, I got kinda irritated that it was me who couldn't see what I had in front of me (especially on unlit parts of the road or on some park alleys I was using to get home faster). That's when I decided to look for something more stable and finally got myself a proper 1000 lumen light. I've rarely used the max setting since it's so damn bright, but it's been a game changer. I feel completely comfortable riding at night in all kinds of terrain, and I also feel the higher setting helps during the daytime with motorists paying more attention to me at junctions. I just don't use the strobe setting because I'm afraid people might get a seizure.
In the meantime, I see a new model of my own light has come up and it's even stronger.
I'm definitely recommending this!