How sharp does it need to be? In most cases, the sharper, the better. The sharpness of your edge is determined by the bevel (the lower the angle, the sharper the edge) and how fine of a grit you choose for your final honing. Since you've already determined your bevel angle many steps earlier, now you just need to know which grit you can stop at. This again depends on the use of the knife. In most cases, go all the way to the finest stone that you own as this will give you your best edge. The only exception would be a knife used to cut soft vegetables like tomatoes, as a slightly more coarse edge will provide more of a tooth pattern for easier cutting.
