Is it not something that AMD are trying to customize the GPU for with 8 ASE (or was it ACE) and 64 instruction que (iirc) or something to that effect to increase GPU efficiency and eliminate any downtime for any CU be it for GPGPU or rendering related tasks?
I don't think so. I think the ACEs are there more for compute tasks. They should help mask latency there and keep the CUs full with stuff to do, but I don't think they'll do much for pure graphics tasks.
But as previously mentioned, high end PC GPUs seem to manage just fine with GDDR5 and latency