Overall I think there is going to be a lot of "old" gpu compute hanging around, and now that writing kernels is a lot easier than it has been, we might as well try and see what algorithms we can get working there.
I originally picked up Mojo for the SIMD, not for the GPU kernels. The SIMD usability in Mojo is outstanding.
Paper on the tool I wrote: https://doi.org/10.1093/bioadv/vbaf292
What's "alignment" in your context. In bioimaging it usually refers to aligning something to a reference atlas (like the Allen Reference Mouse Brain Atlas) or aligning two microscope channels (like the red channel and green channel)