The Alaska will not be easy to make. I am currently working on the Lexington class battlecruiser and I am uploading an updated Colorado.

The Alaska was even a proposal! The construction of the Lexington sounds great!

playable ships
 

I am trying to figure out playable ships. Is the point that you play by commanding a playable ship rather than a submarine? So you float around in a playable U. S. warship, using all of its heavy guns to decimate the enemy targets? (Pardon my elementary inquiries, but I have only played a Japanese Fuso, and that did not work out too well.)

Mid Ship turrents were a disaster in many navies and fleets. The blast damage often caused more harm to own ship than enemy units, and the vibration affected optical sights and intrumsents in the control areas severely. Some of the most extreme examples of WWI did not teach the lesson but the cut backs in the fleet plannig avoided some disasters.

Been finally agreed that the O-class is not implemented by you? Or is it still planned?

I was planning to modify the original Scharnhorst to a design more like the O class, but never got the time becouse of other projects.