Seems like an interesting game, but what I always felt was missing from most pirate games were realistic elements. They over glorify everything and make it feel too cinematic. I would love to see a Witcher-esque Pirate game offering the all-around rawness and completeness the Witcher series has (TW3, to be specific).
I'd give anything for a true Pirate experience with a massive open world, a good story (multiple narratives, decision making, different endings), realistic conditions, large scale ship battles with large crews, more real life elements and more pirate-y additions like (not sure if I'm allowed to say this - gonna attempt to PG-word it) pleasure houses and a wider range of inappropriate vocabulary.
But regardless of my ideas above, I'm going to play it and see for myself - the Steam reviews have gotten me interested.