Thanks for an excellent range of talks on all aspects of HA!
The roadmap concept of adding a community database of metadata to enable better organisation of entities, and more better automatic setup sounds ambitious but worth the effort.
Adding a water leak sensor could suggest adding a “Leak Detected Notification” as a starting point and also include the battery state in a dedicated dashboard. The issue today is (almost) everything gets added to the GUI regardless how useful it is, and that generates clutter as Madelina said.
This is something I’ve seen before…
- Fibaro Home Centre had predefined actions for stuff like fire/ leak/ intruder. Not great, but Fibaro sensors with Fibaro logic allowed them to infer more.
- openHAB added the Semantic Model several releases ago.
On the surface, this is a way to modelHome -> Floor 2but goes deeper to include not just physical geography but also logical structure likeCorner Lamp -> Colour Temptying entities/properties to devices. - You could also argue the community metadata db already exists in several forms. Z-Wave and Zigbee define entities with semantic grouping in both the device discovery process and additional configuration such as “quirks files”. This allows poor manufacturer choices to be fixed, or kit re-purposed (e.g. IKEA remote).
The openHAB semantic model took me several attempts to configure just the physical geography of my home. Way back in time I created floor plans for MisterHouse, and even with them, tweaks were needed. Is the conservatory in the garden? Is the loft floor 2 or floor 3?
Expanding semantics from physical into logical can require more choices which partly depend on how a device is being used. IKEA 5-button remotes seldom are used in the way IKEA expected - DIM UP on one remote turns on a cycle trainer!
To get this to work, mixing community guides (here’s one way to do it…), with semantic data that can be downloaded (e.g. Z-Wave quirks) and local configuration (I’m doing something different but understand YAML) might give a leg-up to beginners but not impede experts.
I’d suggest reading the openHAB docs as an example of how physical and logical can be modelled - the first attempt probably needs lots of caffeine, but that’s where community-contributed data can help.
Thoughts? (please no SDM in UML 
)
If this helps, 
this post!