I just finished it last night and I really enjoyed it. Gorgeous art style, great characters (#TeamClaudia), and I enjoyed the writing and the shenanigans. I didn't realise it was going to be so short, though. It kind of felt like we got through the pilot, and now the real show can start, but... then it just ended. I mean, don't get me wrong, I much prefer they leave it open like this than try to wrap up every last thread in the last two episodes and ruin it like Korra Book 1 (I'm never going to get over Amon), but... well, I just want more. Do we know when Book 2 is coming? Or if it even is coming?
I do hope they'll consider rendering a few more frames next time around, but to be honest it only really stuck out to me in slower dialogue scenes. The action looked pretty good, but more frames would obviously make it look even better.