Now, I read over at Building a Character: Concept and Fluff, that sentai teams wouldn't be appropriate for the setting. Having grown up with Power Rangers, and playing Chroma Squad along with recently watching someone's let play of it, I felt a bit disappointed at first, but then I had an idea for a character that'd allow for the specific elements of sentai, (specifically, the transformations, determination, and martial arts reliant combat of older sentai) that I like while still fitting with the setting of this forum.
The idea is as follows: The character is an alien from another planet, being the only surviving member of a sentai-style team that was wiped out. They flee to Freedom City, being scared for their life, but find they can't resist the urge to help others once again.
This comes with several struggles they'd have to overcome. The first being that their previous opponents, including the weak ones, were purely evil monsters that they could destroy without guilt or consequences, while here the average goons aren't necessarily evil, perhaps not having many other options or being forced to, and not only would they feel guilty for ending the life of a person who was capable of more than just evil, there would be significant consequences to even one dying, no matter if it was an accident. Second would be the difficulties that come with not working with a dedicated team that can cover each-other's weaknesses easily and know how each of them fights. Third would be trusting anyone with connections to criminal activities, even if they were an informant that had no reasons to betray them. Fourth would be dealing with the self-resentment and other symptoms of survivor's guilt. Fifth would be the cultural differences.
Of course, if this can't and won't work, feel free to let me know. I have other ideas, it's just this one felt the most appropriate and the most fun for me. Any suggestions would also be appreciated, but please keep in mind I do already have a fighting style and general theme I'd like to go with for the powers and abilities, and I intend to do my best with that on my own if people think something like this would be allowed.
To be specific, what I have in mind is a defensive fighter that analyses how an opponent fights and allows for battles of attrition, being a distraction, and keeping the pressure off any allies they might have at the time.