And not talking specifically about Amigas, but as a C64/C128 successor. Seems like an obvious plan, full backwards compatibility with their 8 bit machines, plenty fast and cheap, up to 16 MB RAM, they were granted half of the licensing cost by WDC... Yet it never happend! And I think it would make for a very powerful entry level machine in the late 80s and early 90s... certainly more impressive than C65, which to me made little sense by 91'. A GUI based OS like GEOS could have been used/licensed by C=...
Perhaps it would be dangerously close to lower spec Amigas, but I think it made sense to try and build on the foundations of 20ish millions of C64 sold and the huge software library that existed.