Gravity Rush 2 is an overall improvement over the first game.
The new powers make the combat not as bland, the world is still really fun to explore and the challenges/side quests (bar some) were pretty good.
The story is kind of a mixed bag; while it definitely tries more with it compared to its predecessor, I still would call it "great".
The pacing is also pretty weird: for some reasons they decided to put so many stealth missions in the main story and none of them were fun.
Overall I still really enjoyed and I would recommend it, especially if you liked the first game, I just wish more was done with it.