Well, I didn't expect much and that's exactly what I got. This is my opinion of it...

What was wrong with the movie...
Gunn said this was a fresh start and didn't want to rehash anything - and then starts with the John Williams theme and title style of Superman: The Movie. Superman himself ended up on his back either bleeding or weakened more than he was upright. Didn't see enough of Lois and Jimmy was the best thing in the Daily Planet. The rest were there for a name-check. Didn't like the way Ma Kent was portrayed. She's brought up an alien but doesn't seem to have a handle on how a smart phone works. Hawkgirl. Why? Didn't contribute anything and I would rather have seen Dr. Light (Kimiyo Hoshi) instead. Mr. Terrific was good, but his pod was made in the same shop as the Milano - same colour and seating arrangement with a reupholster. Green Lantern. Better than I thought from what I saw in the trailers, but does Gunn know how a power ring works? The light is continuous from the ring, not throwing a gesture in the general direction he wants a construct. Supergirl. Liked the look. I've been informed that in the last 10 years, Supergirl has been completely retconned so I can't really comment on her being able to get drunk, call Krypto hers, or having to wear a coat because it's chilly.
What was good in the movie...
Nicholas Hoult - best portrayal of Luthor in a movie by a country mile. This is the evil SOB I want to see more of. Absolutely nailed it! David Corenswet - not too bad, and I can see him growing into the role, but he needs a script that serves him better. Although I've raved about Hoult, this movie could possibly have been better if they had started with Brainiac.
What was puzzling in the movie...
What happened to everyone else that was in the alternate dimension? We only saw the humans being rescued. What was the point of the two post credit scenes?