Myself, I have been more disappointed with the Cleric, Monk, and Sorcerer from a flavor/mechanics perspective than the Ranger (which is not to say I have not been disappointed with the Ranger. My dislike for the Cleric extends through ever edition with the exception of the 2e Priests of Specific Mythoi/Specialty Priests. The Monk has just been plain disappointing conceptually mechanically throughout every edition, in my opinion (in 3e we replaced it with a variant of the OA Shaman).I know that the 2nd least satisfying class after the Ranger, has been the Sorcerer.
As for the Sorcerer, I dislike it for the same reason that I dislike the 4e Sorcerer and the Pathfinder Sorcerer- I don't find manifesting characteristics of a character's draconic heritage or celestial heritage such as wings interesting in the least and the Wild mage even less so. It has no place in the campaigns that I run which is a shame, because I like the idea of magic in the blood granting casting and not needing a spellbook.