How many output modes should a headlight ideally have?
I'm curious how many output modes you look for when buying a light? This is a question I recently asked myself, as I'm currently testing out a Magicshine Allty 2000 and a Light & Motion Vya Pro Headlight. The Allty has an impressive 17 different unique modes (DRL mode + 4 power settings for left LED only / right LED only / left + right LED blinking). Meanwhile the Vya Pro has no buttons, and I believe only a day/night mode that are automatically selected based on an ambient light sensor.
As someone who rides in the dark, I would think a flash/DRL/ramping power settings would be all you need (maybe 6 total modes?). With some lights offering cell phone apps you could further customize it as necessary though.