With Tokyo, there's extra content too. Orochi Tower being part of that second chapter, which is in TSW. Looking forward to making new morality choices. (Your morality changes your final ability you earn at the end of the Tokyo storyline. So think about it! Unless they don't give us that :^(
To add, on beta we had access to all the dlc investigation missions. Before patron testing. I am hoping they plan on making the story significant ones free.
Vanishing of Tyler Freeborn was a critical piece of Kingsmouth's finale. Answering what the mist was, and your first encounter with the true face behind the main antagonist of the game.
Last Train to Cairo was major in delving into the story of a bomb similar to what hit Tokyo. (Done in Indiana Jones style, very fun)
And the final major one was in the finale zone. Forgot the name, but it delved into the powers people were getting via Anima, and some serious story about Orochi motivations. (Done in James Bond style, including a femme fatale.)