The episode was too dark, for sure. But the culprit (mostly) turns out to be HBO. That streaming muddiness is just not compatible with so much black. It looks a bit better in a downloaded HD format. I'm looking at some torrent screenshots, which look noticeably better, and I'll watch one of these to see how it improves. Either way, they should have tested it, so this was clearly a significant mistake.
The darkness made a lot of battle scenes really confusing and overwhelming in a way I think was intentional, especially when the storm comes in and (for example) Dany and Jon can barely see anything. Daenerys not being able to see the battlefield for long stretches is a pivotal plot point in the episode. Many of the soldiers being in the dark is also important and makes the episode more terrifying.
a wight can't break out of a wooden box but they can suddenly break through their tombs despite being nothing but bones?"
The wight they captured in Season 7 had its hands and feet bound and a hood put over its head. Once put in that box, it was mostly calm unless provoked. When it was revealed in King's Landing, though, it was in fact unbound. I'm going to assume Clegane sang it a lullaby beforehand.
I don't see that big a difference between her jumping out of nowhere and stealing a White Walker's face with her surnatural powers
Seriously? One is set up in the show, and the other is not. The show has done absolutely all the work to describe Arya's powers of stealth and agility, but it has never even hinted that it's possible to take a white walker's face. As I laid out, you'd have to kill a white walker first, and then skin its icy face, which is impossible both because they shatter when killed and because you surely wouldn't be able to skin off one of their icy faces. At that point you're just making an ice sculpture. How is that equally silly as running fast?
I might not remember the space correctly, but the nearest wall around that tree is very far away, no? Or she was hiding in the tree? The AV Club writer said: Did she jump on a trampoline? It's not a lack of faith in her physical ability, but knowing what space they're in
Okay, let's look at the scene and figure this out. First, it's worth remembering that this whole sequence happens in slow motion. And Arya is FAST. The first indication we get is Arya whooshing past the white walkers on their right side. Judging by that white walker's reaction, she's already a bit past him when he notices, heading straight for the Night King. She is running on the ground at this point. When we first see her behind the Night King, she is clearly still running ON THE GROUND. She then leaps from the ground. (Not from the roof or a tree or a trampoline—let's stop being ridiculous, people.) She doesn't even leap that high!—barely above the Night King's head. How have people convinced themselves that this leap is an olympic achievement? What's more impressive is her stealth and speed, which has been established over and over again including within this very episode, and is enough to get past the white walkers but is actually NOT enough (by itself) to get the Night King.