how instantly strong and badass she is implied to be with zero development
If you mean the way Rose grabbed the agent, I think this moment was not so much about how cool she is, but about how scary she actually is, because she is basically Eveline without chromosomal defects, who was trained by Chris Redfield. She is one of the most dangerous creatures on the planet, so they could add the part that a sniper or someone is watching her.
In the same way, a similar ambient is playing at this moment, which we hear during meetings with Eveline.
and what bothers me is her looks, screams tiktok sensation girl, no different from Kylie Jenner and those mediocre celebs.
How so? She looks like an ordinary teenager who wears ordinary clothes. I don't get it.