Agree on Williamsburg/Jamestown/Yorktown - get the pass that is good for all three locations for multiple days. Our CG of choice in the area is American Heritage.
Gettysburg - yes. Plan for a couple of days at least if this is your first visit. We stay at Gettysburg CG on Rt. 116 (Fairfield Rd.) west of town.
And if you get to Charlottesville to see Monticello, also take in Ash Lawn-Highland, the home of James Monroe.
Richmond has beautiful homes, the Virginia State Capital, the Museum of the Confederacy and St. Paul's Episcopal Church (Robert E. Lee, among others, worshipped there).