Cool project, though - don't mean to take away anything from it.
I find the totally self-contained nature of them very appealing because it travels well through space and time, and it's incredibly accessible, both online and offline.
My current side project is actually using a WebDAV server to host a wide variety of different single HTML file apps that you can carry around on a USB drive or host on the web. The main trick to these apps is the same trick that TiddlyWiki uses, which is to construct a file in such a way that it can create an updated copy of itself and save it back to the server.
I'm attracted to this approach because it's a way to use relatively modern technologies in a way that is independent from giant corporations that want to hoover up all my data, while also being easy to hack and modify to suit my needs on a day-to-day basis.
Edit: I sketched out a basic version in JS + Python, it's fairly ok to use. The nice parts about this approach is the HTML files are viewable without any extra services, and the service that enables saving doesn't itself need configuration or to keep state.
The downside is even though you know the current directory due to window.location the API is written in the way it assumes you either want a default location like "desktop" or need the user to navigate to the directory before you can do operations on it (for security reasons) even from a local context. The user needs to select the directory once per fresh page load (if you've dynamically reloaded the current content then multiple saves need only prompt once so long as you save the handle).