Honestlym I don't think I've liked a roster as much as this one since the '04 Patriots. I think there's a very good chance they win the Super Bowl and that they will at the very least get to the NFC Championship game. I will eat crow if I'm wrong, but they are not going to be another Eagles team...here's why.
1. They won some games against good opponents when their QB was just a game manager. The Qb also showed late in the season that he can rise of to the occassion if he needed to. They are one of a few teams that can win both high scoring and low scoring games against good opponents.
2. They won the real offseason championship. Most of the times, the offseason championship goes to the team that signed the best players...which is usually correlated to the guys that got paid the most. More times than not, those FA's end up not being worth what they paid for. Cliff Avril signed a 2 year 15 million dollar deal. At 26, I doubt this is the megadeal he was hoping to get. He'll have two years to prove he's worth more. Same thing with Bennett at 1 year and 5 million. Some same this was a "bet on himself" type of deal. In other words, he didn't find what he was looking for, and will work his butt off to hopefully get more next offseason. Good deal for both sides IMO. They got good players without paying them to the point where they could potentially become content. Low-mid risk deals with high upside.
3. The rest of the roster is filled with young guys. All 4 guys in the secondary are pro bowl caliber and still playing on their first deals. None of them have gotten paid yet. Same thing with their stud LB Wagner and QB Russ Wilson. Red Bryant is a dominant DE who got paid last season and stunk it up this season...Not sure if it was injury or being content...but SEA can afford to dump him now unless he improves or takes a cut. Talented roster with players who should be on the upswing of their careers.
4. Niners are the defending NFC Champions and will be looked at as the big brother of the NFC. Should give the Seahawks even more motivation.
The achilles heal of this team was it's road performances, specifically 1pm East Coast games...but they even started to improve on that as the season went on. This is a strong defensive team with a capable offense. The core of the team is intact, and outside of Percy Harvin the signings were pretty much role players...paying for guys to play a certain role and paying for guys to be a star are two different things...the former being more preferable IMO.
Coaching will be the big question. But looking at the talent of the team, it would be pretty hard for even an average coach to screw this up.