Mechanical identity separation from spellcasting.
Narrow selection of thematic powers that possess great individual flexibility.
A method of utilizing that flexibility to improve aspects of the powers to make them more useful in the current situation.
The ability to always tap into the basic powers, themselves, independent of current reserves of power.
A broad class-based focus on information gathering from people, places, and things which does not require specific power selection to accomplish to represent the sixth sense in general.
Insight proficiency as a keystone identifier, rather than Arcana. Understanding yourself and the people around you is a potent characteristic of psionic characters who 'just seem to know' what people around them are thinking and feeling, even without reading their minds.