Disparity Among Divers
Divers are a mix of champions that were made or reworked prior to the solidification of subclasses and champions that were made with the subclasses in mind. As a result, there is a certain amount of disparity among these champions. Even when taking post-subclass distinctions into consideration, a few champions still differ quite substantially from the others.
Anyone can tell that champions like Camille, Fiora, and Riven are more ability oriented champions. They require timing and abilities to make their presence felt. Anyone who has seen a bad Riven (correction, everyone has seen a bad Riven) knows this is the case with these champions. That said, champions like Warwick, Xin Zhao and Master Yi, the mission is to basic attack until they are dead. These lead to vastly different builds and styles withing the subclass, and treating them as being the same is, I think, a mistake.
That said, I believe that we should further define this subclass, and split it into two separate pieces: Bruisers (I'm sorry, but champions like Garen, Darius, and Illaoi are just better defined as Juggernauts: slow, but impending machines of death and hate) and Divers.
Divers represent a mix of aggression and selectivity. Like many assassins nowadays, Divers must make the most of a mistake, and rely on abuse of mechanics to punish those mistakes. While assassins have better target accessibility and burst damage, divers make up for that with better cc and survivability.
Bruisers, on the other hand, are simply much better at just rubbing their faces into an enemy until they kill them dead. Their damage is very high, both in DPS and burst, but they are ultimately quite squishy champions with a single combat trick that allows them to survive. Their mortal enemy, their nemesis and bane of their existence is any immobilizing cc. In 1v1, these champions are usually unbeatable, and they excel in splitpushing.
The reason I find these differences so important is because treating them the same results in one group being overtuned or one being undertuned, never both being just right at the same time.