All it would take for me is the feature set of an A1200 plus a much faster 68k CPU and PCI/PCI-e.
Beyond that it's all fluff.
I think the developers forget that people like myself mostly want our old software, but with up to date hardware and that they can't write an OS in a reasonable amount of time.
Edit: thats not a dig a Aros, they are doing a terrific job. But look at the history of Amiga OS's, they take decades with the manpower available.
My point was that whatever hardware is made needs supporting software so it pretty much requires our old apps and OS to work out of the box.