I like the henna arrow (REALISM FTW), I like Sokka and Katara's clothes (because I always thought they were a little weather-inappropriate for the arctic), I like Zuko's scar (it just looks damn better. I always thought "hey, year-old partially healed scars aren't that red"), and I LOVE LOVE LOVE Dev Patel.
I think we're going to be okay as long as the special effects hold up.