This document is 🚧🚧🚧🚧.
At a 20,000 foot view, the idea is to turn the route into a component that gets params from the router, turn the model hook into a resource that returns AsyncData, and turn the substate feature into a #match on that data.
This document will soon be updated to describe the routing proposal in detail.
In the meantime, resources are described in detail in the reactivity section. #match is described in the match proposal, and the end of that proposal has a detailed sketch of the basic idea of AsyncData and how it could be used in routing.