I should say that if your concept is just a gimmick, I'm less likely to feel comfortable with accepting the sheet when I release the OOC and sheet format. 

The crux is making a character dynamic that gels with others, but this is also Power Rangers and not Euphoria so keep in mind that you can have layers without having an exceedingly dark backstory. These characters are starting points. I am currently unsure if I will be applying for a individual ranger myself, but I have to see where everyone is at with concepts beyond color.