I would say I'm in this category, most of my least favorite stories tend to involve having to deal with unlikable characters whereas casts I like tend to have a few I like and the rest I feel indifferent to as opposed to loathing. Bad characters just suck the joy out of a scene, even if you have a character you like in the same scene, I find I focus more on the character I dislike because they irritate me.

With that said, I have to like a majority of the characters to say I like a cast. It's a balancing act, but I do tend to like casts where I like everyone and the few I dislike are purposely written to be like that (Algus/Argath anyone?) but if the cast has too many characters I find annoying or the most obnoxious character is a major character with screen time, it does suck the joy out of the plot.