AFAIK the focus with Clone-A is to *clone* an Amiga 500; meaning aiming for absolute perfect reverse engineered chipset for *100%* SW compatibility. The focus with Natami OTOH is to reimplement and *improve* the chipset, which inevitably will mean breaking a certain amount of compatibility. So spec-wise the Clone-A *will be* an Amiga 500 (no ethernet, usb, pci, 256MB chipmem or whatever), while Natami will be something else. Different purposes, different goals.
I think thats correct. Didn't they show the CloneA chip replacements actually plugged into an A500 motherboard at some show where they had a contest to see if anyone could bring something that would run on the Amiga but not with the cloned chips?
Bzzzzt...wrong! CloneA isn't just an OCS compatible device, plan was to have cycle exact versions of OCS, ECS and AGA. In other words, it's designed to be perfectly compatible with ALL Amiga software, not just A500 software.
I imagine the reason you think this is because only the OCS chipset implementation has been fully demonstrated so far. However, there's been more information on the CloneA posted by Jens and Oliver on the English Amiga Board which fills in some of the details. Recommend looking through these posts for a more accurate picture of the CloneA project.