Enrico Pucci, to me, is a character you can sympathize with. He himself thought he was doing things for the greater good, but was ultimately selfish to the core.
Even at an early age, he was stricken with survivor's guilt over thinking he was the only twin to survive his birth. He devoted his life to faith and helping others, most likely to justify his own existence. Doing so led him to the uncomfortable realization that the man his sister was dating was their long-lost brother, Wes.
He tried to hide this information from the couple and tried to separate the brother and sister by paying a corrupt detective to scare them, which resulted in Wes being mortally wounded and Perla committing suicide in the confusion.
Unable to cope with the guilt for his involvement, Pucci fled to DIO and adopted the concept of Gravity: the belief that every event that transpires happens for a reason and cannot be avoided.
So determined to prove that he was not at fault for his sister's death, Pucci did several horrible acts to obtain the Ultimate Stand, which he used to create a world where everyone had already experienced every event in their life, allowing them to know exactly what would happen to them before it happened. They could not change their fate, but Pucci hoped them knowing beforehand would allow them to face destiny with resolve and happiness, knowing that it was an inevitability and no fault of their own.
To me, Pucci represents humanity's inability to cope with the chaos of the universe and their reluctance to reflect on themselves, while being so quick to judge everyone else around them.
Diavolo and Kira are great too, BTW.