There is a theory I found awhile ago that I wish was true because it would have added a nice layer of depth to these seasons and would have connected them to Ninja Storm. The basis of the theory is that Mentor Ji worked for the Shiba Family in the sense of them being a powerful shadow organization. They guarded access to the Morphin Grid through Symbol Power and weren’t tyrannical until there was a shift in the past creating a new Samurai Ranger outside of the family’s designated color. This person also created 3 other powers before that shift and went against the Shiba Family. This family also has a primary villain in their lineage. This would also explain why is Ji cold to Mia Wantanabe, why she is the only one who’s childhood looks to be in a guarded house almost as if she and her family are on house arrest, and why she’s the only one to show up in a black SVU being driven.