One time sink that is a bit obnoxious is constantly needing to update elements corner radius, spacing, etc when designs are changed.
A suggestion I have is allowing numeric variables to be entered in these sections to allow for macro controls across a wide variety of attributes. Being able to create a value that controls font-size, line-height, corner radius, padding, etc… This would let you control the relationships between certain elements and only require editing the value in one location rather than every instance that value would occur.