I've refrained from posting here until I got a better feel for the offense. Here's my take.
The offense had nowhere to go but up from last year. As others have said, Portis had an acceptable if not outstanding year for a #1 RB in a pathetic offense last year. That offense should be markedly improved.
The primary reason for the improvement is the offensive line. In the two preseason games, the most obvious difference from last year is the o-line. They went from a severely handicapped unit, which was dominated by a combination of a weak center, the loss of RT Jansen, and the inconsistent play of LG Dockery, to a unit that is absolutely stoning first team defenses this pre-season. That includes Carolina which has one of the top D-lines in the league. By getting a healthy Jansen back and by adding Rabach, who is playing very well at center, the only weak spot is Dockery, and he's showing improvement. LT Samuels and RG Randy Thomas are solid as always. This line, if it remains healthy, should be on the short list of the top o-lines in football when it's all said and done this year. The line will make everyone better.
As has been widely reported, they've also changed the running scheme to more of a zone blocking scheme which fits Portis' talents better. Portis starts deeper in the backfield and chooses his own holes and cuts. Because of this, you should see a lot more big plays such as the one versus the Bucs in Week 1 last year, when Portis cut on his own initiative to the backside of the play and ran for a 60+ yard TD. They tried to make some changes in that regard during the season last year, but you can only do so much on the fly. They spent the entire offseason on this and are now fully committed.
I haven't read this anywhere, but I also think that the 'Skins are going to take a less-is-more approach this season to Portis, at least to an extent. While he loves the football and will take any carry that he can get, they have the depth at RB to allow him to get breathers during games that should allow him to finish the year strong without overworking him. Unfortunately, this may mean that he loses goalline carries and therefore TD's. But I think he's still going to end up with more TD's this year than the paltry sum he had last year.
Finally, the passing game looks improved. You couldn't tell that to a lot of 'Skins fans who are all upset that Ramsey has thrown 3 INT's and 1 TD in two preseason games, but that's my take. I like what I'm seeing from this WR corps. Just as Gibbs has planned, they're faster, better route runners overall, and they're getting open much better on intermediate and deep routes. As a whole, I think this WR corps is underrated the way that NE's WR's have been underrated as a group over the last four years. None will likely be WR studs for fantasy purposes, but I can see them making plays to keep drives going in a way that they weren't last year.
Despite Ramsey's preseason stats to date, I see a guy who is making plays in ways that he wasn't last year. And even if Ramsey doesn't get it done, Brunell looks like a different guy from last year - I'm starting to believe the stories about him being injured last year because of this. One of those two guys should be able to lead the offense successfully.
Overall, this is not going to be a top offense. I could, however, see them end up among the top 10-15 offenses in the league by the end of the year, which is more than a sufficient platform to allow Portis to shine.
Here are my Portis stat predictions:
290/1480/11 35/280/1
So I'm predicting 1760 total yards and 12 TD's.