Access is not that great. You typically have catwalks at the middle and aft end of the hold but not forward. Container doors are usually obstructed by the framing and stiffeners necessary to combat the torsion stresses.
Hatchless ships are typically of the feeder size. The biggest I’ve ever seen were the ACL ships which are Con-Ro designs.
These big boys have big hatches though a disturbing trend has been to build a ‘water resistant’ versus a water tight cargo hatch. This means there are longitudinal gaps between the separate hatches on top of a hold where in the past there was a gasket seal. It’s a real head scratcher but the class societies keep signing off on it. My fixed CO2 operating manual says to ‘wet tarps and seal the gaps before releasing CO2.’ If you can tell me how to do that with cargo already on deck or how to keep them seated on the back side of a positively pressurized cargo hold, I’ll give you a shiny nickel.
The pictures are very disturbing. This reaks to high heaven of unreported IMDG. There should be no reason flammables were knowingly loaded that close to the accommodation space.