I think she is, actually, and deliberately meant to be. Until she does something scary and then you remember what she is. But she’s clearly very charismatic and appealing and funny and cute by design.
It depends on who she’s up against. Much of the time she’s killing (I hope that’s not a spoiler) people we don’t care about and in those situations we’re fine if she succeeds and in some cases even want her to. But when she goes against the good guys, I think they’re still more rootable. So it’s a fun watch because you basically get to feel where the show’s leading you without also feeling guilty or contrary.