Oh, I'm starting to warm up to this topic!! Yes, the story is a rich resource. But also the hanger appears in the movie, most notably as the question mark pressing into Ennis's face as he hugs the shirts.
Not a phallic symbol but a powerful symbol of sexual potency is the beans that Ennis loves and Jack tolerates. This symbol, only mentioned in the story, is expanded (hehe) in the movie for effect. Beans are an ancient Asian symbol of potency. You may recall the story of Jack and the Beanstalk where Jack planted some magic beans which grew into a GIANT beanstalk that reached up into the sky to the abode of a GIANT. Possible clue to the origin of Jack's name?? ??