Yes it is over-engineered. Heck, even WordPress is engineered. Blogs are essentially static pages with the comments as a moving part (i.e. dynamic). Most blogs can happily leave on a static web folder if bound to something like Disqus or whatever you decide to use.
It's true. I've over-engineered my blog as well to be isomorphic, but then I realized there was zero need for client side functionality so I've rendered it all static via a simple crawler. Much easier to deploy and serve with NGINX. Comments are powered by Disqus.