Well she's canonically a callous soldier who believes that murder to purify the bloodline is not just acceptable but good and a bigot towards anyone not of that bloodline, including the PC, so maybe some of us prefer other companions for legitimate reasons? Not that there's anything WRONG with wanting to keep her around for RP or entertainment purposes, of course 🤷
In contrast, the blazing inferno with a heart of gold (or of hell-machine if you want to get all literal about it) that is Karlach is both my favourite video game character in years and ideologically consistent with the character I'm playing, at least in my first playthrough.