So I was initially pretty bummed out that FFG made the missing blue line a "feature". It makes Reinforce a worse action in a head-on joust because it's easier to be to target either section of the C-ROC when you use the firing arc as the divider. But I decided to actually check out the lines of sight in Vassal and compare to the Gozanti. It's not nearly as bad as I thought.
Above are the C-ROC (red) and Gozanti (green) base shown side by side. Also shown are the LOS at each extreme to both the fore and aft sections. The area between the rulers on either side is the area where an enemy ship is able to target BOTH sections of the ship. The area is pretty much the same for both, but it is pushed down toward the fore in the case of the C-ROC. This means, as I said, the C-ROC is worse off in a straight on joust because it's easier for your opponent to just target the section that isn't being Reinforced. However the angle isn't as steep as I thought, so in practice I don't think it will matter that much.
Below are the two superimposed on top of one another (I did this by hand so it doesn't look perfect, but it's close enough):
I still think it's silly that FFG isn't owning up to their mistake and instead are making a permanent change to the ship, but in reality the change is not as bad as I thought.