I don't see a long road back to being good. I think the Sox can be competitive next year, with a few good pitching acquisitions and the offense performing up to expectations as a whole. I would keep all the position players who are under contract for next year, unless they get an offer for one that they can't refuse. The offense is set with a good core of young players mixed in with some veteran experience. The only hole would be 1B. There's no sense in disassembling the offense and creating more holes to fill.
The focus this offseason should be 100% on pitching. Pick up Buchholz' option. Sign 2 starting pitchers, one #1 type and one #2 or #3 type, to go along with Buchholz, Porcello, and Miley. Kelly could be a #6 guy or he can be put in the pen. Rodriguez, Johnson, Owens can be called up when someone inevitably gets injured or falters. Alternatively, sign only a #1 guy, or pass on Clay's option, and let Rodriguez start off in the rotation. That doesn't give us as much depth though.
As much as I would hate to lose Koji, he is our best trade piece among those on the current roster, outside of those I deem untouchable. Perhaps Kelly could fill the roll of closer next season. Add as many inexpensive, yet solid, BP arms as you can, and see what sticks.