The only truly hateable team to me is Baltimore. On so many levels they are bad. Just really atrocious people involved there.
Despite their weird hatred of us and their heartbreaking upsets of us in the SBs, most NE fans have a healthy respect for NYG because many of our grandfathers grew up Giants fans before the Patriots were founded in 1960. The Jets are not competent enough to be hated. I've hated many Steelers players and many Steelers fans, but the franchise itself is fine. I used to hate everyone when I was younger and drunker. Yankees, Lakers, Pistons, Jets, Steelers, Colts, USC, Texas, etc.
Not sure at exactly which point my legit blood boiling hatred turned to relative indifference, but I reserve my hate for very few teams now.