Why 4 SPQ-9A? I could see two, maybe. I think there is some general confusion that SPQ-9 cant "see" through the mast, as I've seen a few personal designs where more than one SPQ-9 is used because of this perceived problem. The mount on the Virginia worked good, although there was a little bit of a blind spot behind the ship, it wasn't bad enough to be worried about mounting another system to cover it. I think this is evident in the fact that, as far as I know, the USN never mounted two of these radars on a ship for this reason. I do think the radar would have been better served being mounted higher on the mast on the nuclear cruisers since it is primarily a surface search radar. I don't think the mast from the Spruance or Tyco's presented any kind a blind spot for this system, but I could be mistaken.
Anyway, I really like the overall platform of this cruiser and I look forward to future updates
PS, here is a conventional powered (alternate history) cruiser I'm working on from the same time period