I used to do "big data" and "cloud" computing when it was called clusters.
Did you run one process with multiple threads across all of those machines, or was threading less of an issue once you started thinking about distributed computing?
I can say this with a certainty: Anything other than a compiled language with low level facilities is a pure waste of time and money.
Isn't that what Numba does? Compiling Python code using LLVM and being able to understand numpy data structures? I'm still not sure I understand what threading has to do with this. The OP said threading was an issue, but threading doesn't
While with Java you at least get some safety for big projects
Safety? Job security?