Unfortunately, parapsychology is a hazy and not too well defined semi-scientific field. Essentially parapsychology is about how the common mind encounters and deals with uncommon and unknown experiences.
If you thought psychology is messed up, parapsychology is many times more so. Parapsychology is the bastard child of psychology, metaphysics, superstition, logical thought, limited imagination and fear of the unknown.
Whether parapsychology develops as a semi-scientific field depends on the scientific ability of psychics and the psychic ability of psychologists - in other words, it depends on you.
The big question of parapsychology is: "How to objectively perceive the subjective?"
It sounds like a paradox, doesn't it? The good news is that this is a yin-yang thing: every subjective has a little bit of objective in it. Even essentially subjective experiences have a degree of inner consistency, inner structure.
As it stands, psychic parapsychology is either a big gaping hole or a great opportunity to evolve the scientific method itself.