Yeah, I can't think of any character off the top of my head I truly dislike. At worst, I'm indifferent.
But on the other hand, I don't know if I have a true favorite. I have several characters I like better than others, but ultimately no character that I like more than the rest. My several dear characters are Ginjou (though a bit less, since his betrayal. but only a bit!), Orihime, Chad, Grimmjow, Komamura, Renji, and Ulquiorra. (i have a thing for lost causes, as you can see) Probably some others, but these are the first that spring to mind.