Removing the original OS would be a bad idea at first.
1. Then why not just run AROS?
2. Compatibility with old apps wouldn't be good
3. You're just going the AROS route again with 3.1 on x86.
I was looking at something more like:
Take a more advanced OS that matches well, say Haiku.
Get Amithlon working on this rather than Linux.
Make use of ClassicWB or other distribution and the users own ROM.
You could start releasing right here.
Amithlon would become more of a UI than the OS, like early Windows or XWindows.
Instead of peeking through a keyhole with special x86 extensions, expose the underlying OS to AmigaOS.
Make use of AROS code to slowly integrate them better making Haiku more Amiga like and AOS more native, eventually negating the need for ROMS, etc that can't be distributed.
Part of my reasoning is that Haiku is more of a spiritual successor than most other OS's, but is far more advanced.
It has SMP, memory protection, virtual memory, datatypes, responsive UI, it's multi-media centric and has a good selection of drivers. It also boots to a usable desktop in 8 seconds. (not counting BIOS crap that can't be helped)
Anyway, that's what has been kicking around in my head.