Staying with the AMIGA-like computing experience and the idea that this could be an ARM based one I would like to make things a little more concrete.
The Pandaboard is a step in the direction I was thinking about ARM-wise, and so are consoles custom chip-wise. Merging these together in a small keyboard form factor with specs like these:
CPU: 2x ARM Cortex-A15 Quad-core
GPU: Power VR SGX543MP8 / 8-core ARM Mali T658
Direct hardware access is a must, as is hardware uniformity, so code can always be optimized. The hardest part would be the OS, it would have to be of BeOS quality in its ability to effectively use the hardware, keeping it clean and simple.