Which essential kernels of info need to be represented on structured Commons, and where does this info need to live?

See https://commons.wikimedia.org/wiki/File:Structured_Data_on_Commons_-_which_information_goes_where_-_version_2017-10-31.png for a first sketch and proposal, which needs to be refined further with the Commons community.

For instance:

• Can the community come to a general consensus on what properties absolutely are the bare minimum required for a MediaInfo entity, and which ones are optional?
• Properties like the location where a photo was taken: is this specific information stored on Commons MediaWiki, Wikibase@Commons, or is it a link to a Wikidata Item?

These discussions will be facilitated by community liaisons, starting from Q3 2017-18 (Jan-Mar 2018).