To be honest, I don't even fully understand what are the use-cases for integrating python with spreadsheets right now. I use both of them separately for different things but cannot see what it can be good at doing in an integrated environment.
I use spreadsheets for all kinds of bookkeeping, and very often there's some data you need to fetch once when a new entry is created, be it stock prices from a webpage or calendar entries from Outlook. LibreOffice's python scripts are great for those cases, because the tooling is just plain better than VB. Alas, VB is still necessary for formulae.
Isn't it simply a more mature language replacement for VBA scripting?