I maintain, they have nothing wrong.
For the Mustang it's because those guys call bugs something that is not a bug but a current limitation.
The mustang can't store manual packages because it has no room inside for it. It's not a bug but a limitation of the actual alpha because you can't store for now manual packages in the closed cargo that Mustang, Aurora and other little ships have. As the Aurora have an inside room, you can use it for manual packages.
Glitching and having boxes falling through floor are not specific bugs to starters ships but for all ships. Calling a "quality pass" on starter ships is useless because to get rid of those bugs, you need to debug the engine for all ships, there is not one specific engine for the starter ship to debug. The one thing that makes more bugs for boxes in the Aurora is only because the inside room is so tiny that you have to be carreful when you place them on the floor. When you understand that you have to correctly places the boxes on the floor not in front of the door or the seat, you have a lot less bugs. You can replicate the exact same bugs when you place boxes on the wall/doors or stack them in a Nomad.