Since the subject of regearing arises periodically, I thought it would be interesting to see how various folks deal with the subject.
All of my bikes have custom chainring and cog sizes which I have selected to fit my own needs.
I typically go for a low gear in the mid-40s (gear-inches), a top gear in the mid-90s, and an average ratiometric progression of about 6 or 7 percent through most of the range, sometimes with a larger jump at the very top or bottom. I live in an area with light winds but some hills.
What works very well for me:
50-42 / 14-16-18-20-23-26 for club riding, recreation, unloaded touring; superb
47-38 / 13-15-17-19-21-23 for same applications -- not nearly as nice a ratio progression
49-46 / 14-16-18-21-24-26 equipment-constrained on an old classic; a bit stiff in the low end
45-42 / 13-15-17-20-23-26 for commuting and general transportation