So far he’s been shown to be a lecherous perv who takes advantage of women’s emotional baggage when they’re down… but I have to admit, I’ve got a soft spot for his “you want to talk about it? You know, since you don’t give two damns what I think” bit with Mary Margaret. I honestly have no idea who he used to be.
I’m drawing a blank on guesses for Dr. Whale too. I figure if people were robbed of their strongest positive quality when the curse took hold, then maybe he was chivalrous in Fairy Tale World? A knight, perhaps?