I'd love to have 256-way servers available, for maximum performance. These would be incredibly competitive, surpassing the best available offerings from AWS and GCP at the moment (whose normal offerings top out at 96 and 224 CPUs respectively).
While I'm sure some applications will want a huge amount of memory to go with that, in my case I'd be happy with around 2GB per CPU. It'd likely make sense to have a "high compute" version in that range, as well as an offering with 4+GB per CPU for more memory-intensive workloads.