Watched last night, I didn't enjoyed as much as everyone, but it probably is mainly due to personal preferences...
The only major criticism is the convenient plot point towards the end: [BLACKOUT]Ares revealing himself when there was nowhere to go if he hadn't[/BLACKOUT]. That felt kinda sloppy, like the writting get to that point and then couldn't solve how to end the movie without it.
The other thing that bother me was that's mostly a hero's journey movie, and felt predictable, BUT that is something that I usually don't hold against a movie, quite the contrary. When people that watch tons and tons of movies predict coming plot points, it is mostly that the plot points fit in with the overall plot, wich is a good thing. Probably with me was that the predictions lead to stuff I didn't like, or very cliche ([BLACKOUT]Ares' carbon copy Darth Vader moment "join me and we will rule together[/BLACKOUT]). This is where it might just be personal preference bothering much, and nothing more.
But mostly, it was ages above what the DCEU was delivering. It might be flawed, or not, but if it was, at least the flaws were minor decisions and the movie is mostly consistent and true to itself.
I would rate it 6/10 or 7/10. I can't see how the rest of the world think it is the great. But still, it is a solid movie.