More focused on the design aspect than particular tech but feel free to share how you arrived at your design.
I am writing a new SSG (really a meta-SSG) because all the others make me depressed when I start to use them and I never wind up launching a site. (For instance, is Markdown any easier than writing HTML, really? I can find all kinds of templates for Hugo and they look like :poop_emotion or :dog_emoji)
My plan is for sidebars and navigation elements to be client-side dynamic because it is just crazy to respin every page on the site because I added a new page and now all the sidebars need to be rebuilt. The sidebars could be a svelte app or they could just be plain HTML imported with HTMX. It doesn’t matter much —- there’s going to be a Python system that packs up the metadata from all the sites.
The basic plan is to build on top of bootstrap with SCSS and not really put a lot of effort into chrome but rather be free to have big images (photo galleries), math with polyfills, visualizations with D3.js, etc.