I feel pretty much the same as the general sentiment here, though I wouldn't call it 'mediocre.' I was entertained for the first 3 and a half hours...
I did think it was way overly long though the last half our of the movie I really, really just wanted it to be over. Just completely lost me and I didn't care anymore. Never a good sign.
ummm spoiler alert? lol not sure how we're doing this anymore
It all just felt really, really, really tired. And man, people ripped on Superman for destroying a city, lol, how many millions of humans died in this film? At the end in the news thing they're all like; It's all good, cuz Magneto, you know the guy who killed millions, changed sides right at the end and saved us! rofl...
But really that was just amusing, it wasn't a big thing, it was just common ground that I wasn't invested in at all.
Why cant they ever give these villains a goal other than destroying the world? Seriously, the good guys ALWAYS win in the end, and they have to, because the alternative is the destruction of the entire world, so the end is never in doubt, obviously they aren't going to let the whole world get destroyed, hard to have a sequel when you do that... Why not have one film where the villains goal isn't global destruction and instead make it a more obtainable goal like just to make a bunch of money, and let them win! That would be interesting. Who will have to balls to end one of these superhero movies in complete despair, Empire styles...
This is why I prefer Japanese Anime over American superhero lore, because the bad guys win all the time and the heroes die, and as sad as it is, atleast it's freaking interesting!
And I'm not talking about Marvel "deaths" where at most it's an ancillary character that nobody cares about, or they just kill a main character and then bring them back to life inexplicably, which is worse IMO than not killing anyone at all.