Generally speaking I'm kind of getting bored of instantly OP MC isekai of late, but this series is great, so far. I guess it's because it's so cute. She doesn't behave like a 19 years old person at, but it's better that way; it would be creepy with that little girl body and the mind of some 35 years old otaku dude. However, neither is she acting like an eight years old, which is a detail necessary for the story to progress.
Anyway, this is cute, very much so.