I just came across the Composer Button Bonanza component which seems to do a lot of what I want.
Mostly, my users would love to find the easiest ways of doing things that are hidden now, like strike-through or footnote. It sounds like with a more WYSIWYG-style composer this might be improved.
Additionally, there is confusion about the “preformatted text” button that appears in the overflow/cog menu when someone is using a touch screen. As an code-oriented community, I would want that button to be always visible.
On the other hand, I realize that some buttons are not applicable to other communities, so a way to customize these to cater for actual needs would be amazing. I mean, I love a good mermaid chart and I can imagine some communities will be using that option a ton!