Yeah, I get that quite often. I think because they know I’m around most days (at ridiculous times of day and night) to answer questions and I have ways of finding solutions! 
What I can tell you is that there are no alternative WYSIWYG editor controls you see in “edit mode” for RapidWeaver or Stacks. These are hard-coded into the app and the plugins. There is no developer API available to us (that I am aware of), that let you change what buttons are shown to you or customise what they do.
I do agree with other comments here (and elsewhere) that the Styled Text and HTML Code page types could do with a major revamp for RapidWeaver 9. For all its problems, the new Gutenberg editor in Wordpress has proven quite influential in how people can edit content.
So far as code is concerned, it’s a great shame, because there was once a rather clever and sophisticated page type plugin available for RapidWeaver called Code Complete. This is the only reference I can find to it now:
It was previously developed by Michael Robinson @faceleg and released alongside a couple of other highly useful page types like Meta Mate. I used to love his Code Complete plugin, because I am rather old-school and predominately do a lot of content editing for websites in HTML or Markdown. So the features formally on offer in this Code Complete plugin were a big upgrade over the HTML Code page type bundled with RapidWeaver.
This thread from 2016 suggests Code Complete got taken over and is developed by someone else. But I cannot find any other mentions of it. Alas I think Code Complete was too far ahead of its time - back then a lot of people did not care for HTML code or Markdown.