Caroline is definitely pronounced with a long I and I don't think it's hick-ish at all. That's how my sister pronounces her name (she gets Carolyn a lot too and
hates it). Every other Caroline I know also pronounces it like you. I knew a guy from Washington state who had a sister who pronounced it like Carolyn, but otherwise I've never heard of it being pronounced that way. They are 2 different names to me (related, obviously, but still different).