I was watching the movie for the 4th time and noticed something very interesting but welcome: Optimus actually uses the rocket boosters during the battle. He engages them when he leaps off of Grimlock's back and yells "I'll kill you!" at the drone he's attacking. Thought I'd point this out because one of rhe few real gripes I had with the movie was that the jet boosters seemed to come out of nowhere. Seeing them used in battle made me feel slightly better about their inclusion and role in the ending.