If fonts were cars, the Arial Light would be fitting for night driving. I imagine it having a softly illuminated dashboard and headlight-cancelling rearview mirrors. Reading too should offer the same adaptations–flick a few switches to give us the best fonts in pleasing shades so we don’t ruin our eyes.
Twelve-point Comic Sans MS, if it’s not banned outright the silly font just might be critical to learning. A psychologist at Princeton University found that the harder a font’s readability, the better the recall. A block of text set with 50% leading is easier to read than text having no line space where ascenders and descenders touch. The point size can be used as a unit of measuring type and line space. For regular newspaper and book text, 8pt to 12pt usually satisfies.