I set out to create a Lego compatible modular cargo ship design.  This was created with the assistance of AI to create an OpenSCAD model. 

My goal was to create separate ship pieces, and hoping to make something easy to print (no brick studs) and able to interconnect easily (adding technic holes).  Eventually would like to expand to part list to create more complex designs.  In the current design the top deck is 16 studs in width, 9 bricks in height.

I've included both the .stl files and OpenSCAD code that were used to create these.  The OpenSCAD is highly adjustable - hoping to expand upon this for other designs.

In this my version #1 and first model posted.  Some tweaks are still needed for the lower technic pin holes (depth), watertight connect points, and efficiency (less material) and overall interconnect strength.  Sharing for input, feedback, and others creativity!