Ah, Nuju Metru, it's great to see you back and MOCing! And I see that you've made a character from your Kentoku Archipelago BZPRPG. While I never got around to joining that one myself, due to having a hectic school schedule, let me say that I am very impressed with the entire storyline and parallel island chain to Mata Nui and the Matoran race that you've come up with. Your worldbuilding skills are outstanding.
Now, onto the MOC! First of all, you did very well on the proportions, with the poseable torso working to give her feminine hips, which is nice. I really like Nihi's sash, but like Black Six said, I feel that the green color clashes a bit with her other colors. I would actually say that solid Mata blue would work well here, to complement the small bits of it on her lower arms.
Other than that, the balance of blue and gold is excellent, and I commend you for your use of the sapphires and the Ninjago straw hats! The great Rau works pretty well with the crystalline armor -- I'm glad that you're going with the lighter version from Dalu instead of the darker one from Nokama, although that mask would have blended pretty well with her dark Metru blue parts. I see that you're using the awesome new Mixels joints for the hands; it's just a pity that Exo-Force robot claws don't come in gold or blue (same with Hordika necks, for that matter). Oh well, at least she has a sweet looking wooden staff.
This is a fantastic build as always, my friend! Can we expect to see more Dasaka (or Dashi or Datsue) characters from your RPG in MOC form any time soon?