I've seen a lot of discussion on this, and some people agree that in the late 80's manga scene, psychic powers were pretty "cool". And Araki just kinda twisted them into ghostly beings tied to the user. A lot of the early Stands in Part 3 have basic psychic abilities, like Telekinesis (Jotaro), Pyrokinesis (Avdol), and Clairvoyance (Joseph), to name a few. Later Part 3 and onward they become really surreal and bizarre, in good ways and bad.
There's not a lot you can do with the Ripple without keeping Vampires and Pillar Men relevant. DIO is still a vampire, but a Ripple user without a Stand wouldn't stand a chance in Part 3 and beyond.
Storyline wise, I'll spoiler this as it relates to to stuff in and after Part 4 Diamond Is Unbreakable:
Araki adds the Stand Arrow, and ancient artifact that imbues people with a Stand if it pierces them and they survive. Someone gives it to DIO, who uses it on himself, triggering the Joestar bloodline's Stands as well.