Oh are we doing season rankings?
2 > 4 > 1 > 3 >>>>>5/6
I'd put 5/6 on the same level. They both have their good points but those are few.
As for 2, people often don't like it because of Lila. But they never mention DOAKES. Doakes/Dexter was one of the best things about the series. And I actually like Lila so season 2 just becomes the best season for me.