I don't do a lot of frontend work, but I'm glad to see more of this stuff popping up. Anything that combats the normal framework insanity is a good thing in my book. And this looks like a really cool idea. The default routing approach is an awesome idea, swapping the entire body by default is also really interesting. It seemed odd to me at first, but the more I thought about it the more it made sense.
Thanks! Yes, swapping the entire body by default felt like the right trade-off, it covers 90% of use cases with zero configuration, and you can always narrow it down to a specific fragment (or group of fragments) when needed.