Hopefully, Luke does something beyond what others have done before: learn (or at least try) to reconcile both the Light and Dark sides of the Force.
The Jedi and Sith we know from the movies are basically branches from the original Jedi. The Jedi try to suppress the Dark while the Sith try to destroy the Light. Each side treats the other as a corrupting influence rather than something that needs to be better understood.
We have seven movies showing that this doesn't work. Luke seems to realize this after Kylo Ren's betrayal. Seeking the first Jedi temple (before the Light and Dark sides split) might be Luke's attempt to find a different approach.
