Not myopic, but I do have some eye problems that limit the correction I can get. This may make me in the minority, but it also means that dark background defaults are not a positive experience for me. Text on light backgrounds is is crisp, while dark backgrounds looks like it's been badly anti-aliased.
With regards to brightness of the monitors, I keep it reasonable - about 25% of what the monitors could do.
When I have no choice, I also tone down the brighness to ridiculous low levels. On some monitors, even 0% is too bright (hint: change the contrast then, some monitors will dim the backlight some more).
With regards to brightness of the monitors, I keep it reasonable - about 25% of what the monitors could do.