Although the concept is interesting,there's two major points to consider.
1)The aim of the WinUAE guys,(I would think),is to come up with the most accurate "classic amiga",(OCS/ECS/AGA), emulator available.
2) Whilst the AAA,RISC, & other Amiga developments might've died with Commodore,the fact is the pantents for those designs undoubtedly still lie with Amiga Inc. or Gateway or somebody.
Regardless of if they never physically existed,(Well AAA design boards had been in possesion of David Haynie,I think.), if someone came out with a software emulation of those proposed specs they might claim the project was a copyright violation.
Lawyers love this sort of stuff-it keeps them employed all the time!