The Hermit is a classic story character, and particularly so in the role of the Hermit Guru. So adapting one for a significant role in a game is certainly something to consider. Most hermits in games will necessarily be NPCs, as they are solitary loners by definition (though Sally here seems to have managed an exception).
When it comes to playing a hermit, there are many directions you can go in. They can wise, or cryptic, or insane, or repositories of forgotten knowledge, or oracles of the future. Or all at once! The wisdom and knowledge parts are good reasons for PCs to seek them out, and the just plain crazy ones can be amusing planned wilderness encounters in remote locations.
Luke: How do you know all this stuff? You've been trapped on this swamp planet for years.
Yoda: Here with all the Jedi of the past I have been.
Yoda: Connects us all, the Force does. Watching you I have been.
Luke: Right, using the Tree. Of course.
Yoda: Ready to face your mother, you are not.
Luke: Yeah. I kinda figured that when she cut off my hand.
Yoda: Complete your journey to the Light Side, you must.
Luke: Journey to the Light Side?
Yoda: The Dark Side you know of. What do you think is casting all that shade? Hmmmm?