Why would you start with the Linux kernel if you don't want Linux? It's not like it's made of unicorn concentrate or something.
I never inferred its anything magical!!
If you reread the post you quoted I gave the Linux kernel as an example. There are quiet a few alternative OS kernels that could also be used, any of the BSD's, QNX etc. The point is not to try and reinvent the wheel but use an existing OS kernel that can deliver all the hardware support that ANY modern OS should have ie. memory protection, SMP, etc. The kernel can then be used as a basis for an amiga like os, just like Amithlon runs 3.1 on a Linux kernel.
This is the only way move even think about developing an Amiga for the 21 century, OS4, Morphos and Aros will never (without serious investment) appeal to anyone who never owned a classic machine. And Natami whilst a cool piece of hardware is just a classic and should not be considered as a way forward, just a possible replacement for dead machines.
In all honesty after reading the posts in this thread the best thing CUSA should do is play the Bruce Banner walking away music, go their own way and leave the Amiga community to dream of past glories and what could of been.