[swaggyBoatswain]

I am comfortable with making anything in Adobe Indesign.

If you are going to make things in Indesign, it should be as a last step process, after the full draft has been made. Otherwise you will slow down your writing by a lot.

Quark is rather outdated IMO, little has changed over the years. It has terrible UI and native keybind controls

I would use some flavor of markdown + some notetaking tool that supports it. A good example would be gitbooks.io, there's other ones out there too.

Latex & Variants is what has always been used for textbooks. Can't go wrong with it