Pretty much all of Marvels new characters deserve better. Like 99% of them are put out for a single book and forgotten for two factors. Either they are being out-shined by the headliner that's put in to help 'push sales' and ends up sucking all the oxygen out of the environment. Any time meant to grow the new characters is pulled instead to making an already popular character do something for people to clap at. Shark Girl in Spiderman and the X-men is one of the best examples. Because the villains are weird Dinosaur obsessed super scientists she is able to appeal to their baser instincts as a shark as they are more or less prehistoric. She says that even though it was just to get in to betray them, and even being a bit repulsed by them, that she did enjoy getting legitimate attention for physical attraction as she hasn't gotten it since becoming a shark. This is sadly done through text of her directly stating it and relegated to half a page because as a 6 issue series the book has no time to breath at all, and Spiderman and the X-men is one of the best at not steamrolling characters because the new X-team was at least somewhat established already.
Other than that, new characters are forced to play second banana to Social Justice. Either the messaging in general or a direct stand-in character in particular. Most new characters being introduced have to contend with characters being 'pushed' like America Chavez or Squirrel Girl, and I dare you to find a comic book with those two in it that doesn't make you want to puke.