Brown being in for Wichmann is a big difference in the run game. He is much better there, and actually was ok last week in pass pro too (which is where Wichmann had him before). So there is a chance we can see some continued upward trend with the OL, which is the key in all this. IF they give Gurley a crease he will dominate, plain and simple. You just cannot get in the groove as a back when you're facing an endless amount of hits from unblocked or poorly blocked defenders.
Trouble right now, either way, is with the defense. Where this team goes overall comes down to the defense and OL in my estimation. Still a chance they can get on a nice run if those things get good production.