of the ending which was solely on the kid rather than on a love connection between Blunt and JGL.

I think Rian did a great job in terms of not going the conventional route and having JGL kill old Joe and raise the kid with Blunt, as a family. Instead Joe has to make a far tougher choice, one that puts the focus squarely on the child's development with a mother vs without one. Obviously there are variables involved in whether the child indeed does turn out well, but the movie veered away from all of that (particularly in regards to the Time Travel, loved Jeff Daniels tongue-in-cheek rant about it lol. Great writing.) and just focused on its main themes which imo made it that much better.