Pro: Hailee Steinfield's performance, the 80's vibe to the whole movie including references, the cheezy military subplot with John Cena felt right ( beacuse it was the 80s) , the heartfelt feeling of the movie, some of the humor, the tonewas great. When the movie wants to be heartwarming or serious it handles it correctly. Bumblebee as a character, G1 looking autobots. The relationship between bee and charlie's character felt great and fresh. The action scenes were great, all wide angle scenes.
Con: The pacing throughout the the 3 acts. Towards the beginning and end the pace of the movie becomes incredibly fast whereas the 2nd act is very slow. I wish they explained why is there a war on cybertron and what is the decepticons reasoning to attack the autobots. One character felt not be needed in the movie and felt out of place. It isn't about transformers really but about an entity and its relationship with someone that is different that it meets. The screenplay also felt very reminiscent of ET and feels like it throughout the movie.
My nick-nac:
I also found a big plot hole, optimus send bee to set up a base for bumblebee but he never does anything about that.
Overall for me I give it a 3.5/5. It's the best transformers movie ( that's not saying a lot ) and is a great holiday movie to watch. My problems with the movie are really dealing with the main plot and pacing but the performances and overall feeling of the movie makes it good.