I still don’t like her at all.
When she was first introduced, I did like her. A different villain that fights not with strength or magic, but with ideology. Not original in itself, but for FIM, it was something new and different, considering all the previous villains were your typical “big bads” that were magically powerful or what have you.
And then what do the writers do with her in the finale? Turn her into a generic power-crazed villain that just wants to fyayk up the main character and nothing else. And then heel-face-turn reform her into a protagonist.
Adding her to the main cast carries the same problems as when people were suggesting Sunset Shimmer should be added to the main cast: She doesn’t bring anything new or interesting to the group. She’s just a rehash of S1 Twilight: OP magic, bad at friendship. It didn’t help that almost every single episode followed the same formula of her trying to solve a friendship problem with magic, then messing it up and having to fix it.
Overall, she is just boring and bland. She doesn’t shake up the group dynamic. She doesn’t do enough to set herself apart from the other characters. She has very little to her character outside of “OP magic, bad at friendship, dark past”. She just feels like a slightly-different Twilight.