The stowage bins were for barrel cleaning rods, and they will be there by the time it is finished, just one of the details like vents and electrical boxes that have not been added yet. Cesar had it's barrel cleaning kit mounted on the deck just aft of Cesar turret, while Anton and Bruno had theirs mounted on each side of the Anton.
As for Gniesenau, I am not sure. You really have no idea how much time and energy I have put into this and I intend to have a good long break when it is done. But the saying goes, "In for a penny, in for a pound." It would be a shame to do only one of the sisters when the other could be done as easily, relatively speaking, but it will definitely not be until after a break.