I'd probably give it a 6 as well. I just got out of the theater, and I can't help but feel a bit disappointed.
It's not bad, but man this movie is way overstuffed. There's like 4 hours worth of movie here, cut down to a little over two hours.
The fundamental issue for me is that there's not a single, meaningful throughline in the film that gives it the feeling that things matter. There's no weight, no stakes, no meat on the bone. It tries to be serious like, two or three times, but it never follows through and usually goes for a joke instead.
Despite a lot of creative character designs, cool tech, bright and colorful visuals, and plenty of nods and deep cuts from comic books, I just didn't care that much.
No single character is on screen long enough for me to feel like I know or care about them, including Superman. It's as if we skipped an entire trilogy of movies and started with Justice League Part 1.
There's just so much going on and so little time. You've got Lois and Clark's relationship, Krypto, his parents, the Justice Gang and it's three members, Lex Luthor and his group, Ultraman and The Engineer, The Daily Planet and all it's members, a Kaiju, black holes, anti-proton rivers, mutated monkeys, a war between Israe... two fictional countries and a crazy dictator, interdimensional floating eyeballs...It's all just too much. The tone is all over the place and the writing isn't strong enough to overcome that.
The jokes were sadly very hit or miss in my theater, only about three or four got some laughs. And you can tell that the film really wanted to be funny.
The soundtrack was also very mixed. The classic theme is great, but there's a lot of punk rock here that clashes with the tone of the film. Not bad, but more suiteable for Guardians.
That's not to say it was all bad. The visuals are nice and bright, which definitely invokes classic comic book superman vibes. The film is overall well casted and there are a few touching moments here and there, along with plenty of action. It's not boring or bland, it keeps things moving, and Superman does feel human and somewhat relatable.
It's big and bold, a swing in a totally different direction, and I do commend that, but man it just did not come together for me. It does lots of weird shit, but I felt nothing.
If you really want to see a 200 million dollar saturday morning cartoon on the big screen, you're going to love it. Especially on a big IMAX screen. But if you want an actual movie, with actual characters and arcs, you might be disappointed.