The wait is over (at least if you are curious enough to try a beta version). I just released the first rather stable beta release version of my Nested Properties Editor and Advanced Metadata Templating Plugin. The plugin is still called obsidian-eln-plugin because I initially developed it for the purpose of an Electronic Lab Notebook system. However, the architecture of the plugin could be used for any type of templates. Further the NPE which is part of the plugin can be used completely independently form the note and metadata templating system, however it is planned to make the NPE aware of the note templates to improve metadata consistency.
More details about the plugin you can find in my post in the “Share & showcase” section:
Plugin: Template Architecture and Nested Properties Editor for Complex Metadata Structures