With or without the plugin, I’d still be using CPTs simply because there will page pages and content for each of these things. It’s very hard to create a “page” in WP if you don’t have a post or a term where content can be easily edited. The plugin I created is based examples posted on this site and to be honest, there is not much to maintain unless ACF alters the way it stores values for relationship/post object fields, and I don’t see that happening. If you have any problems with it just post an issue on either the WP forum or on github.
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