In the core rulebook for RIFTS, we have the Burster. He is a psychokinetic Master Psychic that specializes in the control of and over fire. As we know from issue #19 of The Rifter, there are other psychokinetic manifestations; while these are all variations of the Burster, that's not relevant. What is relevant is that once you have one form of psychokinesis you're soon to have all of them.
A psychokinetic is a psychic whose powers involve the direct application of will to control and manipulate physical forces- and yes, fire counts. These powers are always at the upper tier of what Psychics are capable of, so they usually manifest early in life (e.g. Firestarter). Due the power involved, unless these youths have some adult guidance on hand (and that guidance isn't useless) those manifestation episodes often produce traumatic episodes which greatly shape the lives and fortunes (and personalities) of the emerging psychics.
Playing a psychokinetic, therefore, should account for that emergence episode; untreated trauma routinely opens the door for psychological damage and related issues which (in Palladium terms) often translate to Selfish and Evil Alignments. A Good-aligned psychokinetic can be counted upon to have the necessary nurturing and support at that critical time, allowing them to mature into a healthy individual without letting their power distort their perspective (as being a psychokinetic, while putting one well above ordinary men, hardly makes one a truly god-like entity).
Because psychokinetics come into their powers so early in life, and their powers are so potent and applicable, psychokinetics are people whose identity builds around their powers. Their self of who and what they are, their worth as individuals, is built upon being a psychokinetic much like a Cyber-Knight's identity is built around being a Cyber-Knight. Losing their very specific quality of being a psychokinetic, which they developed and honed at the cost of developing a mundane skillset, often results in severe loss of self-worth that can escalate into full-on collapse until either the powers are restored or a suitable substitute is found (and that is not easy for someone so potent as a psychokinetic).
So, putting it together, playing this sort of psychic is akin to being one of the more potent X-Men: your life, from the get-go, is about being psychic in a very specific manner. You think in terms of your powers, you identify in terms of your powers, and you've worked with them so much for so long that you don't have much in the way of mundane skills should you lose those powers. Such very narrow, but deep, expression of top-tier psychic powers that focus on the control and manipulation of physical phenomena creates an individual akin to Storm, Magneto, or others like them- regardless of Alignment, they will never see themselves as ordinary people, but instead as something else, and act accordingly.
(Note: While much of this can apply to Mind Melters, their breadth of powers seriously changes how they relate to and perceive their environment, and merits a separate post.)