AoU has some pretty shots but I would not call its cinematography a highlight.
It seems that most of the MCU movies lose a lot of value with every re-watch, once you realize how hollow and formulaic the movies are.
The only MCU movies that get better with each watch for me are TWS, Iron Man, and Ant-Man. CA and IM2 remain just plain good, the rest are literally the same movie step by step and aren't really any fun, just tryhard, tilting from mediocre to terrible, maybe Guardians had some originality but it was outdone by Ant-Man in its premise imo, Guardians feels very stale to me at this point.
Not coming from a DC fanboy perspective, I'm sure it could look that way, just my honest opinion as unbiased as I can be, Marvel has been losing appeal both in comics and movies lately, other than the movies I mentioned above, the rest feel like an extension of Agents of Shield.
Marvel being "fun" just sounds like a meme to me at this point.