Tordanik
(Tobias Knerr)
3
Amazing to see progress with this project! 
Reading the types of items in the Implementation section, I have one request: The OSM wiki is not just for tagging documentation, and I feel the OSM Wikibase installation should likewise not be just for tagging documentation. I previously mentioned the potential usefulness of item types such as User group and Software, to make the data that’s currently in the infoxboxes machine readable. Very similar benefits (external tools are currently forced to parse wikitext, we could eventually generate tables on the wiki instead of maintaining them by hand) would apply here.
Some brainstorming regarding tag and key items: It would probably make sense to get inspiration for properties from the existing KeyDescription and ValueDescription templates. Properties such as “requires” and “implies” would seem straightforward, as would a Wikidata link. The status and statuslink field could likewise be modeled as properties. Additionally, it would be interesting to store default units and other established units as properties of a key item.