I also have a Droid Maxx. This is one of the MOST maddening things to me. I have intentionally and meticulously spent hours making sure that all of my contacts show up with photos. I can't seem to solve this one. Prior to the last update that combined SMS/Hangouts all photos were correct. Now some of my contacts no longer even show the name, just a phone number. When I touch the stock photo it shows the person's photo and their name. No idea how to fix it. Not everyone has Google+ so this is not going to work. I'm giving this app until the next major update with GV being integrated and hoping it's fixed.
Has anyone else come up with a solution?