DOM Apps should use TextBoxes, TextAreas.
Games should use SpriteFont. First the basic Font that comes in SpriteFont is NOT meant to be used unless your doing retro games and you need black. You should ASAP switch to a different font. Do a forum search for GiveYourFontsMono.
next make the Font BIG. I mean 72pt big in the GYFM program. Scaling down will retain quality. Scaling up loses quality.
As for Unity. Unity may use two different version. Font Rendering and Sprite Fonts. I usually Tk2D Font system used and there sample Fonts use big sprites ie 64x64 per letter.