If you are not too deeply wed to LaTeX, you should consider the Typst app and the related Typstry.jl package.. I recently did a 200-page book heavy in figures and found it worked well. The markup is Commonmark-like.
= Chapter or section
== second level header
#note(side: "inner")[margin note.]
#wideblock(side: "inner", figure(image("figures/fig35.svg", width:120%), caption: [Plot with Optional Elements]))
The colors are set using a combination of techniques called a ternary operator and a comprehension. The way to read this line:#index[ternary operators]