The real issues for me are as follows:
1. Seattle moving to a more man-press scheme. I think they can do it, but it will be an adjustment, and it opens you up to more screens - which Denver is very good at.
2. Their grabby defense. They lead the league in penalties. They'll cheat and pull knowing it only gets called a third of the time. Denver's receivers need to know if they are going to "let them play" we need to push off, block early, and cheat just as much.
3. Turnovers. Denver wasn't fantastic at protecting the ball this year. Seattle is +3 on give/take in the playoffs. Though they only got one against the Saints, so three have come against one team. If Denver turns the ball over, it will be difficult to win.
4. Protection. You spoke to this a bit, but not the other side that seems to be getting ignored. Denver has handled some good defenses and handled them easily. The Broncos have allowed 0 sacks. What isn't being talked about is how the Seahawks have allowed Russell Wilson to be sacked 7 times - at home. Now granted, both New Orleans and San Fran have top tier pass rushes, but Denver is just a sniff behind them - and has been all year without Von Miller. Denver has been able to sack the QB the last several games and this is going against good offensive lines and All-pro QBs. On a neutral field Denver should be able to harass Wilson.
5. Intangibles. Denver has overcome quite a bit. And I really liked their workman approach after the game and how they've been pretty quiet. The Seahawks have been mouthing off and celebrating like they already won it. They're press conferences they've been putting a lot of stock in that preseason game like "we just need to do that again." Denver got smacked in the mouth then. I am hopeful the Hawks see the AFC, and our team by consequence as inferior. I suspect Denver comes out with a lot of intensity and is up for the task.
I see us losing if: If we turn the ball over and they are able to pressure Manning. If they officiate the secondary pretty lightly and we don't fight back they'll hold our receivers, sack Manning and give their offense opportunities. In those instances they will eventually get Lynch going and it will be a long day. I also could Harvin and some explosive special teams plays going their way and taking us down.
I see us winning: If we get a lead and make Wilson have to beat us. You alluded to this before, but if you stop the run and get some scores right away, you put the whole game on Wilson. That's a tall order for him. Wilson hasn't been asked to win the game for his team very much this year. I could see us getting some turnovers when show blitz and drop nine into coverage. I could also see Holiday finally breaking one.
It should be a good game. If Denver is physical and protects the ball, we should be able to win. If they buckle down and force a few, we will probably lose.