I think that Aros 68k is slow is not true (anymore), at least when using it in WinUAE. I tested Hollywood 4.8 in it and as example the "aquarium"-demo was (almost) too fast. Wazp3D, what I use to integrate Warp3D is directly supporting underlying hardware.
What is true that it (or at least was) not optimized for classic hardware, so speed mainly depends on the processor (68060 recommended) and makes no use of Blitter...