I'm going to agree with everyone on the lack of female characters. While it had more than Ninjago and such, there were only 4 or 5 major ones, plus Macku and the Voya/Mahri Nui matoran whose names I can't remember.
Also, speaking of important characters, the lack of sets for the REALLY important ones. The Great Beings needed sets, not to mention the fact that I always think of Cthun when I hear Tren Krom, and the Artakha Bull from the Metru Nui rahi beasts book when I hear Artakha.
No judgement on my bullish views of your gods.
And that the Mistika were just the worst sets imaginable. The Phantoka, sure. They were cool, and I really liked Pohatu's spinny thingamajiggers(please no judgement again). I won't lie that I didn't like the orange, though. Brown needed to come back. Personally, I'm fine with yellow just because that means more Keetorange and I like the color.
There are a lot of other tiny complaints that aren't noteworthy.
And also the fact that there wasn't enough ways to make feet not slide on big people and the enormous feet that Hahli Mahri and Tahu Mistika had.
PleZe forgive me for my transgressions against your religion of Bonkle.