I think anywhere we specify unit values that are subjective we should at least us some consistent system. In this case we're using `0.6em` which translates to `9.6px`. When using a `16px` base font size I stick with `4px` "working blocks" and go down to `2px` segments only when necessary. The vertical padding will also play into the `line-height` so I would prefer that we have some rhyme and reason to these values, `0.6em` seems very arbitrary here.

…but like I said this is a side note and not part of this PR :P