An un-piratable ship isn't worth 72 million when it only has 1500 cargo. And the Kusari Yacht would be pretty good versus pirates with its current stats. I don't doubt that it can take on gunboats if piloted well.
Based just on reading the infocard descriptions, without any stat knowledge, I would expect the Yacht to be the powerful ship and the Kusari Luxury Transport to be the one good at smuggling and running away unscathed. I'd also expect the smaller ship to be the better smuggling ship and the larger ship to have the larger cargo hold.
