I don't like Hilary at all but never liked her so her behavior makes me even more. She is money grabbling witch.
It usually comes down to the writers. In that case the biggest villain is the less liked, but in my opinion on who's doing the less than stellar acting and does not fit the part lately would be Victoria. I don't think she fits that classic looking woman with the great body who's running a big company, but then her role could change.