Visual centring

A heartfelt plea to template designers: please be aware that centring, e.g., 15° does not work, visually. You probably need to add a thin or en space in front, so that the number is centred.

Problem is exacerbated by using typefaces where 1 is narrower than 2. . . numbers should always be the same set width.

I disagree - numbers should be displayed according to the font you are using. Many fonts use kerning where the letter/number spacing varies according to the letter/number width. If you want monospaced text then make sure you use a monospaced font.