It really brought out her inner insanity

^ Yes!

Totally symbolic with Azula. Her hair went messy because she had driven away her servants; in the same way, her personality went messy (for want of a better term) because she drove away her friends.
It's fascinating how the character who professed her independence and perfection (and the idea that trust and faith in others was for fools and weaklings) actually fell apart without the people she would always have professed not to need. And the fact that it was that very attitude (the whole 'fear is the only way to ensure obedience') that drove them away in the first place. Her entire psychological state was a house of cards that was always going to fall to pieces once one piece went out of place. Damn, she's a fine character.
Kuvira rocked the messy hair look, no doubt, it just had less artistic weight behind it.

Oh I absolutely agree; the symbolism with Azula's is amazing. It's also amazingly ironic as she had this desire for perfection...during one of her first apparances she got mad when one hair was out of place, now look! Her hair is a mess, as she slips further and further from perfection her hair slips further out of place.
As you mentioned her messy hair also parallels her messy mind frame.

That's something I love about Azula. The irony of her downfall; she became all the things she thought to be weak. The fear she used to control people was what lead to her defeat. She longed for control over others she spent even have control over herself anymore. She's just so fascinating. Nice card met ephors by the way. And a very symbolic house of cards it was. It was the fact she didn't get the love and support she claimed not to need that bought her down in the end.

Don't get me wrong Kuvira was pretty awsome in the hair regard too, but as you said...not as deep or complex.

Both

Agreed