Luke in A New Hope turned from a simple farmboy to a hotshot pilot in a matter of hours, so I don’t see how it is any worse when Rey does it.
And Rey has lived on her own on a hostile planet for years. Her knowing self-defense and weapons use makes sense. It was a fact that was even set up early on The Force Awakens when she defended herself using her staff.
I think the most you could say about her is that there’s no way she could have learned the Jedi Mind Trick or the Force Pull she does near the end of TFA so fast. But all of that happened under J.J Abrams watch, not Rian’s.