I strongly agree with the author's experience. I recently totally redid my personal site with Hugo so I could simplify it and learn technology at the same time. It's absolutely great if you want a landing page and blog, really terrible if you're trying to actually do anything custom not related to the layout, however the layout tools are plentiful.
May be you should try python pelican [1] with its simple model and static site generator. Another option is Lektor [2] for complete custom design.
Yes, I have heard of both Pelican and Lektor, I see that they both have plugin systems that allow you to hook in custom Python code via signals / events, should give them a try too (especially Lektor, which is newer, and which I know was written by the author of Flask et al).