Re: 'programming styles from different languages are (to a varying extent) supported'
Multi-threading is pretty useless in Python unless you are launching system commands, any real parallelism has to be done using multi-processing (multiple processes), and is far more difficult to get right. It's more akin to writing code for MPP systems in that all data has to be transferred between sub processes using slow mechanisms.
On Linux fork allows the sub processes get any existing data already calculated in the main program (although it can't modify anything not explicitly shared), but on Windows each sub process starts as a clean sheet and all data it needs must be sent to it. Unless you are doing a lot of processing with a small amount of data, there's a big risk that multiprocessing ends up slower than just using a single process.