Redrawing the 6th
The most likely scenario I see playing out is Goodlatte will pick up Page County from the 7th and Frederick/Winchester, Clarke, and Warren Counties from the 10th. The one cautionary note on this scenario is that in each redistricting the Roanoke area has been more and more diluted in its congressional pull. I mention this b/c in 1982 the Roanoke area refused to support Kevin Miller of Harrisonburg after he secured the GOP nod from the Roanoke candidate and led to the victory of democrat Jim Olin. If the area still is adamant about the 6th district being a Roanoke seat, there could be problems. With a new district like this one, whenever Goodlatte retires; the GOP nominee would undoubtably be from the north-central Valley. With the GOP powerhouses of Frederick south to Augusta, the Roanoke area would little hope of getting their guy (or gal) on the ballot.
In light of this, some have proposed that Goodlatte will be drawn into Rick Boucher's district to beat him and perserve Roanoke's power in a congressional district. Under this scenario, all of Roanoke County, Salem and Roanoke City would be put into the 9th along with a good portion of Botetourt. Then the 5th would pickup the 9th counties along the NC border from Galax to Martinsville therefore dumping more of Boucher's former constituents into the 5th.
Even so, this scenario has risks as well. First off, if Boucher was able to make inroads in Goodlatte's base in Roanoke City, it could spell disaster for Goodlatte. Also, the counties that would be drawn into the 5th are some of the most conservative in the district while the weaker counties like Montgomery, Pulaski and Buchanan would still be present in the 9th. Also, this new 9th would probably be much more moderate in an open seat contest than it currently would be.
A third possible scenario for the 6th is to completely destroy the 5th district and start over. This would involve giving the 6th all of Roanoke, Montgomery, Bedford, Campbell, Lynchburg and east to Lunenberg County. The 9th district would then run along the NC border from Martinsville to Mecklenburg County. Franklin County would likely be drawn into the 9th if Goode still had the seat, or into the 6th if he was not. This would leave the new 5th as a Shenandoah Valley seat of Frederick south to Rockbridge and over to Fauquier and Culpeper. This would setup a Valley seat, Roanoke seat, and a conservative 9th.
This scenario sounds the most logical, but Goode probably wouldn't want his district destroyed either. Also claims of gerrymandering would likely come into play with this third setup.