Will cargo be mass and size? For example, will some cargo need a Constellation or bigger due to the size of the load, even if it only weighs one ton?asked by Ralph

So yeah, a ton of feathers is obviously a lot more bulk than a ton of lead, for instance. So yeah, the cargo descriptions on the ship stats are giving you a general idea of how much that ship can add to its mass before it struggles. But yeah, the volume matters as well.

The mass matters, but he was also asking a question about size, as far as the volume of the containers. So it'll be both, right? So there might be some containers that only can be carried by the larger ships?

Yep. So size and mass matters.