I'm not entirely convinced that Kuvira is the villain in season 4.

Lets look at what we've seen from her in the trailer. All of them are just stills of her, either standing in front of banners or action shots.

The banner behind Kuvira says "President Kuvira". In the 3 years since we've seen the Korra gang, I assume that Kuvira has stepped up as a leader in the shaken earth kingdom and won presidency. Although she looks rather imposing (who wouldn't in that metal clan armor with all those guards?), I am not certain that she is threatening.

One shot in particular of Kuvira that confuses me is this: http://i.imgur.com/JJFO60A.png. Like the source OP of the image, I see a friendly stance, not aggression. It's a very odd thing to put into the trailer to depict her as a villain.

We see both allies and enemies in the Mech suits and fighting against the Mechs. We see Zhu Li, Suyin, and Mechs behind Kuvira. We see them attacking Bolin and each other. There's more to these Mechs than we are seeing currently.

Basically, I am not seeing enough evidence to say that Kuvira is without a doubt a villain in book 4.

What are your thoughts?