Without her daughter, Louise never has the insights that stop the potential conflict and allow for the entire human race to take a major evolutionary step forward.
Keeping in mind that she provided the opportunity for her daughter to shine bright while she was on this earth, it's up to us to decide if Louise's choice was ethical and moral.
Personally I believe in a soul and in reincarnation, that we keep coming back to evolve. It's only our challenges and suffering that allow us growth. There is also this idea of soul contracts - that certain souls sign on for a more challenging path in order for those around them to make more substantial evolutionary leaps forward.
Does Villeneuve make these ideas apparent?
No, but I like to believe they were on his mind as he made this film and then left it open to some wonderful discussion like this. The viewer is left to insert their own beliefs into their interpretation.
Again, this film, for me at least, was less science fiction and more spiritual.