Been going deep on a handful of projects this summer, wanted to take a moment to contribute a Drupal module that solved a problem for us called Canvas Fields - the ability to assign standard fields to Canvas Page entities. Text fields, reference fields, list fields. Why? So we can tag or reference other structures to include Pages in the relationships we need on sites. Maybe you have a need for Views filtering, or Search API integration, or better ways of creating lists of content based on several properties of a Page.
There are some caveats, as not all field types or widgets can realistically be supported right now, but in my limited testing does work and solve the general need.
I have tested it so far with string fields and reference fields, integrating through Views and search. This solves a big adoption gap for us, and next hopefully will be bundle-able Page or ability to add Canvas to any content entity type.
You can try out the module here: https://www.drupal.org/project/canvas_fields