Connie's not a... bad character.

there goes my subscribers.

But honestly, Connie, herself, is not a terrible person. Rather, it what she represents. She's a Mary Sue, I hope I used that term right. And she's not a very good one. She's reminds of Black Clover, a Anime I dont like.
Fans:

Black Clover tries, a bit too hard mind you, be a mainstream anime, by taking alot of cliche aspects of Mainstream Animes. Connie kinda tries too hard to do things that are unreasonably questionable, and is very stubborn in her believes,  even if they aren't exactly correct or plausible. And that's hurts her as a character. Sworn to the Sword was a beginning to a very terrible path for Connie.
If you want to see an more in depth  view of my opinion of Connie Marshwarnen, I ask you humbly that you read a story on called My Homeworld by The_Lovely_Starlight.

Thanks for sitting through this bitch session.
I'll see you next time.

Also,  she hurting my ships and that's why I don't like her.