This DLC is incredibly small, and felt mostly like a waste of time. It's a little bit more of the same kind of things as the main game with mostly the same issues. There are 2 new upgrades not tied to DLC progression, one which is useful but uninteresting, and the other which should have been a base feature of the game without needing an upgrade (I hate useless stamina bars so much it's unreal). There are 3 new enemy types, only one of which is fun or interesting to fight, and one of which is one of the worst mini-boss designs I've seen in a game. The jetpacking is tied to environmental stuff, and is both slow and clunky. The story is also pretty weak, the villain is not funny, and if I hadn't been actively putting off story stuff in search of collectibles and upgrades, I could've finished the story portion of the DLC in under 30 minutes. The underwater "gameplay" feels like a bad joke. The new environments are the best part of the DLC, but they aren't particularly special, and lack the little secrets and side areas that made the main game environments interesting to explore.
Overall, I wasted the 3 dollars I spent on this, and recommend that you don't do the same.