More DSMP fans need to be obsessed with C!Niki because while her story wasn't handled perfectly, her character and story explores some really interesting themes.
The first thing she did after joining the server was declare loyalty to Wilbur and L'manburg. The second thing she did was befriend Eret when everyone told her not to trust them. She was the last one take off her L'manburg uniform, long after the founders had stopped wearing theirs.
She was the loudest voice of rebellion against Schlatt, the most violent protester against his reign. She was treated as nothing more than a minor annoyance for this rebellion.
She saw the tnt Wilbur had placed beneath L'manburg, she saw it and kept it quiet because she trusted and believed that Wilbur wouldn't use it without good reason. After he pressed that button, after he died, she went and found one of his old coats and wore it, despite the pain of betrayal.
Wilbur, Dream, Techno and Phil all tried to destroy L'manburg, but failed. They failed to stop people from fighting for L'manburg. Niki didn't. Niki, L'manburg's most loyal and devoted, killed L'mabburg when she burnt down the L'mantree. L'manburg didn't die until Niki declared it dead.
Ghostbur only showed up once for Niki, despite her being one of the few people he remembered, even after all that time.
"We've been overlooked for far too long."
She's been hurt, and her pain is silenced. When she was suffering for her defiance against Schlatt and Manberg, Pogtopia told her to wait, that they had no room for her. When Wilbur died, no one thought to comfort her for her grief, despite that he was the one she was loyal to, that she joined L'manburg for. No matter how loud she screamed and cried, no one heard her, no one cared.
It's about fire and rage and pain and healing. Her pain and suffering went ignored, and she needed at an outlet, a scapegoat. And she tried to do that, tried to hurt others the way she had been hurt, in a blind attempt to fix things in a messed up way.
Then she heals. She heals with those who she joined because of that anger and pain and wrath. She heals and finds peace and makes amends.
Niki's story isn't perfect, but it's so wonderfully complicated and full of beautiful contradictions. Loyalty and Defiance. Hope and Despair. Forgiveness and Revenge. Blind Faith and Paranoia.
I just think this fandom really sleeps on her a lot.