I just read there's a possibility for more than two seasons, but it isn't for sure yet. That would be great if there were!
At the end of the episode, I saw the whole second season being about Korra's journey to delve deep into the spiritual side of being the Avatar and using that to journey towards figuring out how to get her bending back. Maybe even learn control and a little reserve with her bending since airbending is the only one she knew then. So that was a little disappointing to me. Plus the episode just felt extremely conclusive, so I wonder now which direction the next season will go in. Well, the writers have done a good job so far... I'll put my trust in them.
As for the Avatar State, I couldn't tell if Korra really had control of it or
if it was Aang really acting through her. Like when Aang could go in and out of the Avatar State without realizing it (though Korra wasn't destructive if that was the case like Aang tended to be). Guess I'll figure that out later...
...and on a sad side-note, I guess I should change my signiture. Not like there's going to be anymore new episodes anytime soon