Rather than thinking, “how do I combine a bunch of disparate content, templates, and tooling into a functioning website?”, you might think “how do I start at a functioning website with content and then use templates and build tooling to enhance it?”
I think Jim is onto something here. The more dependencies you have in your build process, the likelier it is that over time one of them will become a single point of failure. A progressive enhancement approach to build tools means you’d still be able to launch your site (even if it’s not in its ideal state).
I want to be able to view, edit, and if need be ship a website, even if the build process fails. In essence, if the build does fail I can still take all the source files, put them on a server, and the website remains functional (however crude).