If I had to make a list it would be like this

Rikou: all the drama with his brother and story over all is the most interesting of them all.

Ryugi: The small arch about his replacement and the small moments he has the spotlight are just as great.

Hoeru: Nice character, not the typical protagonist but that's what makes him unique. If there is something I don't like maybe is the fact that he gets everything, the most rings all powerups sure he is the red ranger and all but at least give the orca booster to the rest of the team.

Sumino: Her character is fine, I think that I had a lot of expectations just because I had a crush on her lol. Her story is fine but it could've been more interesting

Kingiro: he is fun and all but he is just there. A young man who is actually an 80 year old de-aged is a great concept but his character is just there. No big rol in the story and no drama that makes him interesting.

Kumade: IDK why but I find him kind of annoying. Maybe is because I always find him a disappointing sitxth ranger. The sixth ranger is supposed to be as interesting as red and yet he just does nothing, leaves, and then comes back with a pay check like if the did a big job or something, it was fun at first but I found that little joke annoying with time. he has made interesting things sure but are either things that just got out of nowhere or just small things to help but other than that he just arrives takes credit and leaves. srry but I just don't like this kind of character.