A couple of points/questions:
Tacking is not possible against the solar wind, because there is no parallel to a keel or water medium for the keel to push against. If you draw the forces that operate in sailing, you will see that the forward motion comes from pressure on the keel being pressed against water resistance at an angle to the incident wind. There is no water or equivalent to press against for a spacecraft.
Second, I fail to see how any angle of a solar sail could slow the ship down (unless it is already heading inbound towards the source). The incident force is away from the sun/source; you can angle the sail to get some sideways pressure, but no possible angle gives you reverse pressure.
