Header Helper is targeted for two main groups: the first are new RapidWeaver users who aren't comfortable coding, but just want to use an easy interface to make heading changes. The second group are power users or designers who don't have the time to do the manual coding and just want a quick interface to make heading changes.
It allows you to easily apply changes to h1-h6 headings. Edit almost any kind of characteristic for headings there is, including Google fonts. It can even ignore headings you don't want changed. Header Helper is ready for Stacks 2+ and supports RapidWeaver versions 5 & 6.