Oh for fuck's sake, here, I'll do it with just Korra if it'll shut you up, you flippant dicksicle.
- At the series opening we can immediately see that Korra is a headstrong individual with great pride in her bending prowess. Her style and personality are totally physical, something which grates at her teachers. She doesn't have much respect for tradition, but clearly has respect for her teachers themselves. Still, she strains at the confines of her training, and is eager to complete it and fully realize her role and abilities as the Avatar.
- When she reaches Republic City, though, it quickly becomes clear that her sheltered upbringing has left her a bit...well, sheltered. Not only does she have the usual culture shock a rural bumpkin experiences upon moving to the big city, but she's never known want, or crime, or the need for restraint. When she learns of and experiences these things first-hand on her first day in the city, it disturbs her worldview and she wants to stay and try to fix it. Again here we see her longing to be a good Avatar, to live up to the expectations people have in her.
- speaking of, she's also obviously impulsive and impatient. She gets easily frustrated when she makes mistakes or things don't go as she planned.
- like Aang, she's bad at dealing with negative emotions like fear. Unlike Aang, though, who simply avoids the topic like a dodging fiend, Korra buries her emotions and throws herself at the subject, making a great big show out of not being bothered by what she's feeling (even though she really is). It's no mystery why her favored style of bending is firebending, this is a very Firebender way of dealing with your problems; where an airbender would dodge or an earthbender would block, Korra attacks.
- Going back to the sheltering issue, in basically every romance-related thing she participates in it's pretty obvious that she's bad at it. I mean for fuck's same she was asking Jinora and Ikki for dating advice. Growing up in a sealed compound, surrounded by kung fu masters and white lotus guards has clearly not been great for her love life, and her understanding of relationships, especially in The Spirit of Compeitition, seems pretty idealized and black and white and pretty obviously drawing on nothing but radio serials and other media's depiction of it. Hey much like her take on street justice in the first episode! Good guy vs bad guy, bad guy loses, good guy gets credit.
- As the series goes on we see her grow more frustrated with herself for failing to understand airbending, but also that this frustration feeds into a feeling of failure as an Avatar for her. Again, she wants very badly to be a good successor to Aang, to meet the expectations set on her shoulders as the Avatar. That she could neither airbend nor connect spiritually made her feel pretty worthless. Her confident self-image is more fragile than it at first appears, because everything has up until this point gone her way, and she never developed the patience to weather the difficult times, or the humility to properly admit to failure. Learning both patience and humility are the major internal conflicts in her character arc, and although she's never exactly a bastion of neutral jing, she did improve considerably - compare the rally in episode three with the ambush/rally sequence in the finale. In episode three, she wanted to just bust on into the rally, bending blazing, and take Bolin back. In the finale her plan centered around hiding and waiting for the right moment to strike.
- As you may have noticed, a lot of the above focuses around her identity both as a strong bender and specifically as the Avatar. And that should come as no surprise, because being the Avatar has been her entire life. Unlike Aang, or Roku, who didn't know they were anything other than unusually talented benders until they were twelve and sixteen respectively, Korra's known who she was from the time she was very young. She lived in a protective compound, she trained in three bending arts, her whole life up to this point was dedicated to being Aang's successor. So when she loses earth, fire and water, when she is effectively no longer the Avatar, her whole identity, everything she ever worked for, is gone forever. Not only can she no longer be the good Avatar that she had been striving for her entire life, while she lives she's actually impeding the arrival of the next Avatar. If she contemplated suicide, it's no wonder.
And that's just one character. Done off the top of my head, and on my phone, so there's frankly even more I could probably say. But I suppose you'll just respond with more greentext and flippantry, so keep fucking that chicken I guess.