Nice!
That’s quite close to how we use Discourse to manage projects at Pavilion. We use
- Assign for assignments
- Discourse Event for events
- Closing topics to indicate completion
- Categories for “teams” (e.g. each client of ours gets their own private category and group)
- Tags to distinguish “projects” from “tasks”
We also use our Layouts Plugin and Layouts Category List Widget for our sidebar 
I’m curious why you chose not to use the mobile layouts view?
We’ve chosen to hide the categories dropdown entirely (in a theme component). I’m curious if you’ve made any tweaks to the Category List Widget to select specific categories? Or if you’re using the excluded_categories setting? I considered added an included_categories setting (or something like that), as that might be useful to some people.
I actually recently enabled 3 tiers of categories on thepavilion.io to allow for a different knowledge base organisation. We’ve previously had
knowledge
layouts
custom-wizard
category-highlighter
We’ve now moved to
knowledge
plugins
layouts
custom-wizard
themes
category-highlighter
I resisted making this move for some time, as three tiers is more complicated, particularly for plugins and themes to handle. For example the layouts category list widget didn’t support 3 tiers (I just recently added support).
However, we now need three tiers in the knowledge-base for organisational reasons (e.g. we need to pull certain knowledge topics from the api on a category basis). As might be expected in a project / work based discourse the categorisation can be influenced by organisational needs, as opposed to discussion themes in a more discussion-focused forum.