Sure, but for the most part I didn't find them unlikeable or unsympathetic. The show seemed to me to be saying that one didn't have to be perfect, and that being a little loopy wasn't the worst thing in the world. In the last episode, though, the series did morally indict the characters. That episode wasn't one of the best by any means.
Yes, that’s what made the show work, in that the characters were horrible yet somehow we found them likable, warts and all. That’s always a difficult to maintain, most show either make them too unlikable, or too perfect that we cannot relate to their lack of flaws.