I don't think you could make a full book out of Psychics (maybe a book the size of the gm toolkit)
doubtful, I've got tons of ideas in my head for psychics, they feel like an incomplete afterthought, in my opinion.
I feel like the basic system hasn't go much going for it (compared to Ki and Arcane). What kind of things would you like to add?
Edit: To clarify what I mean is, I don't see it having much of a direction to expand in.
more things to spend PP on, like temporary innate slots, increase potential for an entire discipline permanently, nemesis resistance, etc...
more disciplines, psychics have fewer supernatural abilities than any other type by a huge margin.
more personality profiles, how about sensing/intuitive, thinking/feeling, perceptive/judgmental, logical/emotional, worrisome/carefree, perfectionist/slob, etc...
a module for wizard mentalist so that they don't have to buy two kinds of projection
a psychic discipline designed to work with The Gift
special varieties of psychic crystals that have different effects, like some that increase projection, some that favor certain psychic disciplines over others
more info on what a psychic crystal is and where it comes from or how its made.
more advantages for psychics, Arcana Exxet literally has 0 advantages for psychics.
lots of other stuff.