My three most hated teams are Miami, New England, and the Jets. They move in and out of what team I hate the most on any particular week, but they've all been down there consistently.
Even when the Colts were part of the AFC East, I didn't hate them as much as I hate those other three teams. It does have A LOT to do with the Bills, but I would see myself hating all three of those teams even if I was NOT a Bills fan.
As for which one we hate worse, we hate the one that wants to steal our playoff spot. Therefore, my hatred for Miami hasn't been great lately... especially when they beat the Patsies last year (I loved that).
But I will hate all 3 of those teams forever, and I have them in the same category together.