In space, you can manuever the ship however way you want, so having blind spots isn't necessarily a bad thing depending upon what kind of ranges you fight at and tactics that might be employed.
Think LotGH where the ships formed Napoleanoic firing lines. The main weapons were almost always long beams that ran the length of the ships. They were always fighting at thousands and thousands of kilometers, so whatever edge in accuracy or flexibility a turret would lose in power and range.