Kreia was the ultimate puppet master Off subject but they seemed to really dive into oblivion with swtor
Above all, as much as she focused on the dark side, her alignment was believably neutral. At points she'd scold you just as readily for following the dark side as following the light.
Bioware in general fit my perspective of reducing life into multiple choice, so I have a bit of a weak spot for their RPGs. Kreia was a great character for how she was the advisor of a black hole in the force instead of being the black hole herself. Bioware in general seems to hate the notion of The Force being the only guiding principle, showing both sides to have more than their share of flaws. If you ask me, the first Knights of the Old Republic shows us that the Jedi are just as capable of attrocities as the Sith, outright brainwashing a former threat to the galaxy to achieve their own aims. They're only better than the Sith on paper from being less bloodthirsty, but their focus on restraint of what makes a person human (from lack of a better term) makes it no mystery why so many trained in their philosophy turn away from it.
As for her being sucked in, I disagree. As much as she tried to avoid traditions of both Sith and Jedi, she ultimately fell into Sith patterns in the end regardless. Your killing her was simply the path of ascension all Sith go through, a path all Sith suspect on some level to be what will lead to their end the minute they enlist an apprentice, and your killing her still on some level gives her something she's wanted from the beginning. She was a bit of a death seeker even with her interactions with others from her own past, she simply cursed at the notion of letting either path make decisions for you. Her ambition was her guiding principle instead of any sort of faith, and she handled that ambition through a frame of logic instead of philosophy alone.
The game's perspective on influence is a fun one. Characters like Bao-Dur can only truely go dark if you make him hate you while being a paragon of goodness, as trying to make him like you while being dark sided is otherwise an awkward balancing act of exploits. Even swallowed by the dark side, he will never agree with an evil decision, falling into dark power only through emotional appraisal of his own, and as much as you can suck people into your alignment through influence, you can push them away just as easily by making them hate you.
"And she WAS sucked in no one simply destroys the force and it took the exile to bring her down to her failure."
I disagree. Kreia used your character to get rid of her enemies, and recognized the sheer potential for being able to absorb and destroy the force in ways she could never accomplish herself. She knew she herself was a carrier of the force, so she knew on some level she'd have to die. If you kill off the other Jedi Masters, she becomes the last one that needs to be killed to try to destroy the old ways, while if you're light sided and choose to keep them alive she does it to try to push you towards a dark sided inevitability. She was a genius puppet master who aimed to have the example set through your actions shape you into a vision worthy of her own views, steering the black hole towards her aims while scolding you if you begin to stray from her views.
She tried to take down the force herself and failed, even losing a hand after her original fall from grace when trying to do things by herself. She sees your character as a tool she can use, but ultimately bonds into a master/mentor relationship right before her ambition begins to represent the Sith tradition without the history. She even threatens your followers so you won't lose sight of her goals, going as far as probing their thoughts and punishing them for what they think about her choices.
It's debatable if Kreia ever fails or not simply based on the path you take yourself. If you let her become close to you, you ultimately become more and more like her. "The Ends Justify The Means" has been her path from the very start, and her own death is simply a means to that end. The force was always about ripples in a pond sort of views, and she took that view to try to make it destroy itself.
She knew the pros and cons and the actions and the consequences of being both sith and Jedi.
To sum it up she neither wanted either, whist leaning toward sith as you say she became a pariah and in that both sides denounced her.
She conceived a notion at the beginning that she would manipulate anyone in any circumstance in which to destroy the force any way possible.
And yes, Bioware and it's games have treated me viscerally.
And she WAS sucked in no one simply destroys the force and it took the exile to bring her down to her failure.