Thanks, I hadn't heard of that and I will look into it. This is a research setting with plenty of hardware we can request and not a huge number of users so that part doesn't worry me.
If you don’t care about cost of ownership, use CUDA. It only runs on nVidia GPUs, but the API is nice. I like it better than vendor-agnostic equivalents like DirectCompute, OpenCL, or Vulkan Compute.