So I finished the game. Really loved the feel of the endgame, the descent, plot revelations were genuinely surprising, the way they played with the mechanics a bit at the end was fun. Also assuming you were unspoiled, the prehistoric Pokemon having totally different types meant you couldn't rely on your previous knowledge to hit them with SE moves every time. Very clever little design quirk.
A lot of thought and love went into this game. Really good stuff. Wish there were more of those properly animated cutscenes though.