It probably depends a lot on your route. I like 400 or so lumens because several miles of my route is on rolling gravel roads where I might hit the bottom of a hill at 30 MPH and suddenly be on washboard if I couldn't see at least 50 feet in front of me very clearly. I also can come across potholes suddenly at speed, and even large groups of potholes that formed in a day and can box me in - IE if I swerve to avoid one and go the wrong way there might be a series of them that force me in and then I get to where I can't avoid them. For these I might need to see as much as 100 feet ahead, so I can slow down if not avoid them.

When I get to paved roads I don't need that much, 200 would do fine, 150 maybe, but there's no reason to be stingy when I've got lumens on hand for the bad bits anyway.