There's a danger in getting overly concerned with tropes, and the real point is to be free to draw inspiration from where you like while creating something that means something to you.
That's from the Yaruki Zero book, where Ewen talks about anime, but I feel like it addresses a problem we have been having with trying to make the erotic rpg we mentioned awhile back. Or any of our other attempts to make "universal" games, like fursonarpg, and try to create stuff that we don't fully understand the appeal of on the basis that someone will want to play as it.
I think there's something to be said for opening up a game's rules or a setting's canon, to allow for something new to fit in. Sort of like how halfway through the game's run Games Workshop took the unusual step of creating an idealist faction, with clean lines and anime-inspired mecha, in Warhammer 40,000.
But I feel like this stuff is maybe best done gradually, and custom-made on a case-by-case basis. The Cleric and Monk classes in Dungeons and Dragons, for instance, came about because Gary Gygax's friends wanted to play a vampire hunter and a martial artist respectively. Meanwhile, I've been doing an ongoing freeform 40k RP, that started with ideas for my Tau characters and grew to encompass burning_ground's Chaos Daemons and Alias / spinecrawlerrush's Necrons.
Sometimes we think about game design. This is one of those times. >_>b