In a future release, I highly recommend keeping the simplicity by allowing people to browse the basic stats page without requiring JavaScript. Other than that, it is a great project.
Can you elaborate a little bit on the use-cases where this would apply? I can get into the idea that tracking would ideally not rely on JavaScript, but the dashboard? Surely the administrator can enable JavaScript for their Fathom dashboard, right?
Also, as a side effect, it's considerably faster browsing the internet without JavaScript enabled.