I think the issue is that they have a really good young QB. A good RB, and many good WRs. Lots of other pieces too. Not to mention terrific coaches. And, this is their first year in new systems.....offense and defense. And they've done well in picking it up.
I also think that they don't have all the pieces they need for Wade's 3-4 D. But, they'll make some progress in that department in the offseason because they will NOT be spending picks on QB or WR and probably not RB unless it's pretty late in the draft or UDFA.
I think the Raiders were simply overblown and over hyped. They do have a good young QB, but he is a risk taker. They have one really good WR....who can't stay healthy and has become inconsistent. They have a great OLB, but he can't do it by himself. And, then there's the coaching.
You are right in the sense to say that, for instance, if the Rams go 11-5 and make the playoffs this season that next year they will win more games and go deeper into the playoffs. Too many variables such as injuries to ever assume such a thing.
However, the Rams clearly are a solid team in all departments. The most important piece.....good QB.....is now on board. Second most important piece is good coaching. From there, you have a strong chance to have a good record and go to the playoffs pretty much every year.
