WordPress Page All Content In Template Good Or Bad Convention?

It is normal to have some text used in template. Typically that would be pieces of “technical” text, related to interface and which must be in code to be localized.

In solutions meant for public use it is certainly not normal practice to have actual content hardcoded in templates.

For private projects it is more or less — do what makes sense to you.

One question is — if you don’t feel confident managing this content via admin interface and database (prefering it in version control), how are you confident managing any content via admin?

This might be a sign that you haven’t fully figured out how your content workflows meant to be handled in WordPress, be it permissions, backups, or something else.

Also your “empty pages” approach seems fragile. The idea has been explored here and there in the past, for example as Static Templates, but I wouldn’t say it is mainstream in WP development.