I appreciate the interesting shift in direction of the story and Shay is a compelling character but as many have stated before, this game did nothing to innovate the features and mechanics of its predecessor. Which perhaps was the point and they meant to focus on the narrative, however I feel like a story focusing on this new perspective of the Assassins and Templars deserved a better, more fleshed out game. Sadly, AC: Rogue ends up feeling more like a DLC than anything else. Nonetheless, it's still a decent game and a worthy entry to the franchise.
Ubisoft should hire some new historians though, because right after the Lisbon earthquake there was a massive tsunami that destroyed the city further, plus any ships that might've been in the harbor (obviously). Shay sailing away casually is kinda silly.