I think this readme file: https://github.com/elastic/kibana/blob/master/src/core/CONVENTIONS.md#plugin-structure

should mention why kibana.json is important and what information should be in it.

Specifically:

• What conventions should be taken with the version id? Does this show up in the UI anywhere, is there any logic tied to it, or is it purely informational for developers. Migrations I think aren't tied to it, they are tied to Kibana version.

• What is kibanaVersion

• What should multi-word ids look like? Does this need to match the folder, e.g. my_plugin, or should it be myPlugin?