How to work with taxonomies and metaboxes for listing both actor and character

If I’m using a custom post type for a Movie or a TV show episode, I may use a taxonomy for “actors” and assign all the actors related to the work to it, but I’m not sure how can, besides of that, can also add the character the actor is playing in said work. The characters themselves may or may be not a taxonomy, as sometimes one also needs extra space for adding notes, like “John Doe (voice)” or “John Smith (via stock footage). I can figure something like a metabox with columns for each thing, yet I’m not sure how to make it harmonious.