I am going to go all Jung on you as in Carl Jung and Jungian Archetypes. This is because Jung stated there are certain ways to talk about what is as in what is right now and certain ways to talk about change.

It is from Jung that lots of Jospeh Campbell got his idea of metaphysics and of telling stories and pointing out myths often have common archetypes. Joseph Campbell was just simplifying for the masses Carl Jung and other modern 1900s and late 1800s guys. For example in the early 1970s Joseph Campbell collected 600+ pages of essays and editorials and published this as The Portable Jung. Joseph Campbell is more famous for another work of his which is the hero with the thousand faces.

And George Lucas has said a numerous amount of times that this book is the biggest influence on Star Wars. The Hero with the Thousand Faces.

For example this award / speech where Lucas is talking to Campbell in a banquet in Campbell's honor.

https://www.youtube.com/watch?v=bSyyqctan2c

It is The Hero with the Thousand Faces that Campbell explaisn universal myths about heros and aka these pictures / diagrams

https://www.google.com/search?tbm=isch&q=hero%27s%20journey

So lets take this diagram specifically.

http://idea-sandbox.com/blog_images/hero_journey_900.jpg

So Luke at the end of ROTJ has entered the last stage where he is at least a Jedi Knight and perhaps a Jedi Master.

But being a Jedi Master is not the same as being one with the force and being force ghost.

Take for example Luke when he says no I will not kill my father, I am a jedi, like my father before me. In that moment he was one with the force, but you can lose that moment, you can let your history or your emotions or your moment of transcendence leave you. It may only last a second of your life.

But a true master, one before Yoda in Episode 5 where Yoda is a Jedi Master but he makes lots of mistakes, and Yoda at his death bed in Episode 6 is that Yoda learned from his mistakes, he finally got what Qui Gon Jinn could do where Qui Gon Jinn lived after death. Now Jinn could not be a visible manifestatin as in a shiney blue ghost, and his body did not fade away like Obi Wan or Yoda did. But he was still alive after death as a voice or memory or unique essence.

Obi Wan and Yoda learned how to be voice and blue shiney thing. Yoda just could not get it and spent 20 or so years meditating in the swamp to finally get the Living Force (living only in the present as the fulcrum) instead of the Unifying Force (being mindful of the past and future, aka the stick part of a lever where the stick is then enter a blank space and will now create a lever with a stick and a fulcrum where you can move the world.) Put another way Yoda in some ways was the stupid version of Luke in Empire Strikes Back where he thinks to do magic you need to wave fancy stick around to move stuff. Just like Luke thought a jedi must be big and tall not short shrimp twickster. Both Yoda and Luke can see but can't see what is right in front of them. Qui Gon Jinn was better at hearing and closing his eyes and using his hearing to feel the force to center one self, while Yoda was better at seeing with his eyes and using mental imagery to center one self.

Until you unite these two opposites yet not quite opposites you can never be a greenseer who teaches the next generation, instead you may only be a person who occasionally can do it by just doing it, but not a teacher who can teach it to a new student.

There is a famous saying in Tai Chi aka Yin and Yang attributed to Lao Tzu who may or may not be a real guy or may just be a collections of sayings from 500 BC more or less. Aka the timeframe of Buddha more or less and the time frame of the 1st temple destruction and the canonification of the Torah and some of the Old Testament that was history before that period.

When the student is ready the teacher will appear. Now the second part of the saying is often forgotten.

When the student is truly ready... The teacher will Disappear.

So one of the archetypes is the Hero descending into a mystery place so foreign it is a new world, or it can be seen as a place like the underworld or hell but not necessary "bad" form of hell but instead chthonic or earthly or female inspiration. Now this can be told with a male or female hero but often heros in mythology are males entering the chthonic / female realm and not females entering the aether / heavenly / sky realm.

The hero returns, and the hero defeats the trials or defeats the enemy but that does not mean the hero's journey is over. Only a hero becoming a greenseer one who can enter and exit the hell and the material world (the place between heaven / olympic / void / etc and cthonic / undear earth / earthly realm) can the Greensear die and you have to have the Greenseer die for a new Greenseer to take his place and keep the stakes of absolute terror / aboslute victory up with the drama.

Now the Greenseer can die prior to the next generation learning the lesson but then the Greenseer is not really dead but instead the hero learns from Memory that the Greenseer was his teacher, and now he has what he needs to figure it out himself. Aka the ghost of mufasa in Lion King is the Greenseer / Ghost and whether he really existed or not does not matter, he can be a figment of Simba's imagination or a real cloud ghost. Now Rafiki is a teacher but he is not a teacher in this version of the hero's journey but is instead the guide and the teacher is the past memories he had with his father.

A simpler thing happened in Kung Fu Panda 1. The Drama is Turtle Sage dies at the peach tree, the Red Raccoon will eventually become the Sage / Greenseer instead of just the Master but he needs to find inner peace aka the last lesson and get everything he was taught, and Po the Knight who is the student who teaches the master is also the warrior.

So ROTJ according to the Hero's Journey really ended the hero's journey if Luke was a Sage who could become a Greenseer / Force Ghost and not a Jedi Teacher / Master and not a Jedi Knight / Warrior. He finally got it.

But if he did not finally get it, and he was only truely one in the force only for a brief moment than part of this 8th movie is him moving from Warrior to Master or Master to Sage and the Student is going to school the Teacher and teach the teacher something in return.

But will the Student become wise enough that you can kill off Luke, or instead just handicap Luke, or sidetrack him in some way, does not matter. For some reason this is now Rey's journey and Luke story is almost done or is completely done. It doesn't matter.

Now understanding the difference without a distinction is part of understanding what is archetypes and what is not. Aka this picture which deals with the Jungian words he used.

http://jungchicago.org/store/image/catalog/diagrams/Diagram-Self.jpg

Becomming a greenseer means you can access and move around all the circles. Becoming a master means you can go in the self and in the shadow most of the time but not all the time (you may suck at it.) Becoming a hero requires you to access the self and the shadow and use both types of energies in a productive manner, aka a hero / warrior is a creator or a destroyer or a preserver but the difference between a hero and a master is you can do it more than once or sustain it for long periods and then teach others or do it multiple times. The difference between a master and a god is a person who can now fully use the collective unconscious now when I say god I do not mean Christian God though sometimes it is that type of story, but God as in something Sacred like a Damon or a Demon or a Daemon aka Angels and Jjini and everything material and non material that is what a Green Seer is. Now a Greenseer sometimes is a shaman sometimes he is a force ghost, sometimes he is not metaphysical but just wise memories that survive after death aka cultures and traditions.

Now The Hero's Journey can be described in archetypes but another way of saying this is Monomyth. Note Monomyth is usually associated with the male version of the monomyth with a male protagonist but if you want to be true it can also be with a female hero and mean the same things.

But some crazy STUPID people like men's right groups and men's right activist and nuts on twitter associate only with a masculinization of the monomyth with male heroes and females must have stereotyped gender roles. Instead there is a female monomyth with rigid female gender roles.

But how Campbell and Jung and most other people who study this as a coherent philosophy do not associate these two energies with gender roles but different types of knowledge and thus synthesis of thesis and anti-thesis. Put another way crazy stupid people twist original author's meaning and say they know what the author was saying and try to call everyone else wrong, stupid, idiots, blind when they are the ones who truly did not get it. But yelling, negative attacks, being confrontational sometimes ends discussions in a way where they think they won but they really had an end of a discussion for it is not worth arguing with an idiot or a drunk or a blind fool.