I've noticed that most fantasy anime and manga that people end up raving about that have female protagonists end up feeling lacking and at least one area if not more. The main issues that end up popping up are that there is either just not enough effort put into the story and/or character development, or there is too much effort put into certain parts of the story and/or character development which ends up making other parts seem lacking.
This manga however, does not have either of those issues. The story is well balanced, the character development though gradual is still existent and balance, there isn't too much "fan service" if any at all, and the characters all have things that make them feel imperfect and more human. All in all I'd give this a 7.5 out of 10. The only things I can think of that could use more work is the fluidity of the art style and maybe the explanation of how some events are connected to others being a little too drawn out and some being a little too short.