Low, medium, high, and daytime flashing are sufficient for me. I also like the fifth option of a night flashing mode, which can function as a be-seen light without completely blinding people.
Too many options is not desirable for me, as I tend to use multiple modes on the same ride (particularly while commuting). Medium works well for general night riding; I'll use high on super dark roads/MUPs but turn to low to prevent blinding drivers, pedestrians, and other cyclists. A night flashing mode is nice for downtown areas where people are more interested their phones and parking than trying to avoid hitting/being hit by cyclists.