I ended up missing the first hour due to some unexpected circumstances so take this review with a grain of salt. All in all from the second half of the movie I saw I found it to be a generally enjoyable movie, although there are a few qualms with the logic and the film's marketing. There will be some spoilers, but I won't be mentioning any specific details.
The longer paragraphs below are negatives as it's much easier to moan and complain than praise, but honestly the movie wasn't bad. It was refreshing to go back to actual low level, non world ending threats that are still pretty important. The action scenes, for the most part, weren't outrageous, and the humor wasn't absurd like in Ragnarok or off-the-wall like in Deadpool, but was still funny. I liked that they brought in plot points of older movies and reintroduced some old and forgotten characters, as well as some new ones that could play a role in future movies. I don't think this will make it into a hall of fame, but it is a step in the right direction for the MCU.
So to start off with the marketing, the trailer is somewhat misleading. Maybe it was just me not having a good understanding of what was actually being said, but I came in expecting a more gritty, almost spy-like movie where the main antagonist would ultimately be Red Hulk. The first half of that wasn't totally off, but the one pulling the strings was someone else entirely. Some would argue that it was a plot twist, and that it ultimately is a plus for the movie; however I liken it more to "Doctor Strange and the Multiverse of Madness" where they pulled a frog out of a hat and made Scarlet Witch the big bad. Watching the first half of the movie, in this case, may have provided that extra umph to really give me what I was missing however.
Onto the second part, the logic. This world has had a giant green Hulk for the better part of two decades, and in some cases there were multiple hulks. At some point, you would think they would learn that bullets just don't cut it and won't expect handguns, automatics, and drones to do anything. It would have made way more sense for them to evacuate everyone in the area. On a directly related note, the security force attached to the President probably aren't going to open fire on the President and call in attack drones. Yes, he turned all red and freaky, but the Hulk was green and freaky, and he was in the Avengers and ultimately on humanity's side; there definitely would be more than the little hesitation that was shown.
Onto part two of the logic part, the end credit scene. This will contain spoilers. In this scene, the actual antagonist reveals that he has seen the future by looking at probabilities and says something along the lines of "You think we're the only planet out there? Its coming. . ." This was honestly a waste of a scene and a waste of time to watch. I get that this guy has almost literally been living under a rock for quite awhile, but geez man, that's old news. Thor and all the Asgardians are from another planet, the skrull are from other planets, Captain Marvel has been there, the Guardians of the Galaxy have been there, even Thanos. Like, come on man, we've even had multiversal events going on thanks to Doctor Strange and Scarlet witch.