Jung (1875-1961) was one of Freud's closest collaborators. However, when he began to form theories of the 'collective unconscious,' Freud dismissed him as a mystic and their relationship was forever fractured.
Jung's ideas are vast, but his most influential contribution is the collective unconscious: a belief that elements of our unconscious mind are actually inherited and universal. In literature, one of the most influential Jungian structures is the hero's journey (Campbell's monomyth).
Beyond this, Jung also believed heavily that the identity of an individual stems from the conflict between the conscious and unconscious mind. The unconscious would manifest itself chaotically, interrupting the flow of consciousness like an earthquake.
There were additional conflicts between the internal mind and the external world, too, as he explored different 'personas' or masks for people's identities; people adjust their behavior to suit social expectations and norms.
⭘ Balance between the conscious and unconscious elements of the self
⭘ Identification of personas, shadow self, and the balance between
⭘ Exploration of character self-awareness: are they aware of their personas? Their balance or imbalance?
⭘ Anima/Animus - gender balance and recognition
⭘ Archetypal patterns - common for this view, but not recommended (see comments below)
⭘ Individuation - has the character begun their journey to self awareness?
⭘ Never-ending journey to self discover, improvement, growth, etc.
⭘ Dreams -
⭘ Projection
All of humanity, all good, and all evil is contained within a single person
Sophisticated model of the mind
Heavy influence from eastern philosophies
Never-ending character development
Mysticism is hard to take seriously in the academic setting
(Arguably) overcomplicated model of the abstract mind
Archetypes are dismissive and reductionist; produces bad writing that doesn't address the nuance of works and existence
Never-ending character development
[Coming soon!]