Advanced Font Rendering

I noticed this 'problem' while creating a clock with a custom (professional) font; Each letter has its own space, normally two version are used: Metric and Optic, while metric keeps the letter spacing (if support else a default metric size is used), optic ignores them (e.g. the letter ' i ' could be 20px width, but in metric it's defined that this letter has additional 10px on the left and right side, so effectively the size would be 30px)

I'm not sure if kerning is supported, also an option to change the word-space size would make this perfect

(Also, maybe it's worth to look at dynamic weight fonts)

I made a new request, combining this and some more. Hope you don't mind :)