Let me start by saying I'm very much a skeptic when it comes to DC -based movies. After a large number of attempts, starts, and restarts (and some of them major casualties when it comes to storytelling). Also, keep in mind I'm mostly ignorant of the comic storylines and references, same as with the Marvel counterparts.
This particular iteration, at least with this movie-watcher, was a lesser catastrophe than some of the others, but didn't entirely redeem the franchise. It might be an unpopular opinion - especially in those with a high regard of the character, but it failed to impress.
I'll start with the good things.
The setup was moderately okay, thankfully saving us yet another revival of the origin story - briefing us with a few sentences during the opening. The story touches on some very important and relevant social aspects, like immigration, government overreach, xenophobia, and media manipulation.
The casting of Lex Luthor was perfect. That man can play any character thrown at him masterfully, especially the unstable ones.
The special effects were impressive, thought that was to be expected from a James Gunn movie.
The scenes with the Kents are perfect. Whether on the phone, in person, or in mention, they feel - for the first time in a very long time - like real people. The kind of real people that would raise a good man like Superman.
Mr. Terrific - another superhero I've never heard about or known in my lifetime, is a good addition to the line up. But - as I'll elaborate in the 'bad things' segment, sadly his goodness is not enough to balance out the badness of the two counterparts.
Next, the so so things (neither here nor there).
The script had its great moments, but also bad moments (as in rolling-of-the-eyes kind of bad). There are, in my opinion, a lot of assumptions that are made into the script that are not shared with the audience as a tactic to bring surprise to the story, yet some of them seem pointless.
The same happens with some sideline characters - some of them seem pointless and only added for comedic relief (specifically two or three of the Daily Planet staff that have actual lines but don't help advance the story or bring value to it).
I feel the James Gunn signature lighthearted approach to this particular story went overboard. It worked very well with Starlord because there was no real previous history of the Guardians in the general media - at least not as much as the Superman brand has had through the years. Some of the silliness feels forced and out of place, hindering the story rather than helping it.
The whole "Justice Gang" thing is completely out of place. As much as I appreciate Fillion's style of comedy, in my eyes it does a disservice to his character in the film. I'm not sure if it was the writer's fault or Fillion's characterization of it, but the end result is not pleasant at all. I'll also throw in Hawkgirl in this bit. I can't quite put my finger on what it was, but I did not like this character either. So instead of excitement at the possibility of actually seeing a decent Justice League movie in the future, the real emotion is dread.
Last but not least, Krypto. Another casualty of the humor being overdone, with his behavior changed to suit the story-line, and his traditional look changed for some unknown reason.
All that to say:
If you are a super-fan of the franchise, go see it. You might not be as picky as I am since I don't have a deep attachment to all things Superman.
If not - wait for it to stream.