- Sometimes it's hard to identify, but...is Riley a Mary Sue? She butts in on canon events, takes away some of the glory from other characters (think of the 4 different times she took Hiro's place in thinking about inventing and using the microbots), gets a lot of focus from the other characters, gains a superpower and is developing a martial art! I know in universe we have to bring her up to power if she's going to be working with the BH 6, but do you think it's too much?
- Altering moments in canon in a way that's outside of what you'd expect a character to have abilities in is a Mary Sue. Riley's dad works with tech and robots so her coming up with inventing ideas isn't out of character. She's also doing it by accident (in-story) and is more or less Hiro's "muse", bumping him along a path.
Headscratchers / Empathy