I would seriously want to see a game with male characters in it designed by aggressively enthusiastic yaoi fangirls. I would kill to see how the internet would react.

Her outfit is silly. Not prohibitively silly, but it out of place in an otherwise serious and realism-oriented game. She's a mechanic and she has no practical reason to dress like that. Now if Noctis and his crew were a bunch of guyliner'd guys in black bikinis and short blazers there might be room for an argument that it's fair game but they aren't. A character can be attractive, sexy even, without having their agency or ability to be taken seriously away. While Cidney is not a failure of a character just by her design, it creates an impression of the character and her role that the game will have to make an effort to dispel. If she turns out to be the best character ever then that's all well in good but my argument is that she should be able to exist as a sexual and/or dynamic character based on how she's written and framed rather than presenting her in such a way.