Many SDC properties should be added to the file during upload process with Upload Wizard.
At the moment Upload Wizard is hardwired to add several Commons templates, like {{Information}}, {{Own}}, {{FlickrVerifiedByUploadWizard}}, {{Location}}, {{cc-by-4.0}}, etc. Most of those should also be matched to specific SDC properties which should be added at the upload time. We should have more discussions at [[https://commons.wikimedia.org/wiki/Commons:Structured_data/Modeling|c:Commons:Structured_data/Modeling]] about how to model different cases, but Upload Wizard should handle at the minimum case of own work by the uploader under standard CC license with standard date and optional camera coordinates and heading.
Initially the information would be stored in wikitext and SDC, but once {{Information}} is updated we should store such info for basic cases, in SDC only. {{Location}} template is already capable of fetching camera coordinates and heading from SDC, so if coordinates are added to SDC than all that needs to be added to wikitext is empty "{{Location}}".