Yeah, maybe the puzzles weren't very difficult most of the time, but they were quite fun. And there were new mechanics to explore. I say keep the Trines coming. Also, I'm the Zoya player of our group and I really enjoyed the change she had in this one. She's no longer the loner who goes up in the clouds by herself. Now she has mechanics that help the others get to places, like she herself notes at the end. That change of feel was a really nice way to show some character development through game mechanics. And of course we get all the nice visuals and audio that are hallmarks of the series.
One of the rare games that rewards those of us who like to explore every nook and cranny. That's generally how you find your upgrade materials. Very satisfying. Awesome level design. Also very aesthetically pleasing. The only fault I would find with it is the occasional odd camera that makes a couple of the jumps a bit awkward.