In reply to Aaron.

Patterns should be just fine for use in production right now. Because patterns are just custom groupings of blocks, even if the Pattern API changes or old patterns are removed, any changes won't mess up the content.

This should go along with following good dev habits, such as checking if ( function_exists( 'register_pattern' ) ) , which is not yet officially a WordPress function. Other than that, I see no reason not to use patterns liberally at the moment.