[fjtorres]

For text, the widely neglected best solution--known since the 8-bit computer days--is to change the text and background colors to shades of the same color. Just changing the bright-background white default to a light gray makes a bigger difference than dropping the backlight.
Try different color shades and combination: some popular combinations are amber on black, pale baby blue on medium blue, black on gray, or white on black (or gray).
Easy to try, no added cost.