Amazing you are looking at this from this perspective! Really looking forward. Parallelism efficiency (then performance) is the key problem here. But we also don't want to restrict too much and allow diversity of code execution. The ability to use atomic actions by the blockchain would allow this "efficiency" to scale better. Then it's just matter of aligning the current hardware to the software. And that can be done at driver level by manufactures (or in partnership model, like NVIDIA mostly does).