There is no next step. AmigaOS is a dead end. People forget that AmigaOS was a series of compromises. By design it provided a lot of features present on the high end machines of the day by compromising on security and stability while being able to deliver on affordable hardware at the time. It made for a damn nice system during its reign.
The folks who wrote AmigaOS knew from the very beginning that it wouldn't carry on for decades. If Commodore hadn't gone tits up and became a dominant player in the computing world, AmigaOS today would be something completely different than the OS we all love and are familiar with and all those legacy apps would be running in sandboxes, well not really, we would have dropped them long ago just like the mac people don't give a damn about pre OSX apps.
We move forward by writing something better, not by hanging on to obsolete technology.
There was nothing OS wise that was particularly original or ground breaking on AmigaOS. Almost all of the ground breaking stuff was the hardware, which by todays standards is completely irrelevant.
