What do are you using spreadsheets for privately? I never dig deep into their capabilities, so I mostly use them to track expenses within some particular scope, e.g. healthcare. When I recently wanted to compare several loans and estimate our financial situation several years in the future, I wrote some Python code and used a Jupyter notebook to enter parameters and make plots. Has any of you done something similar using spreadsheets?
On a side note: I didn’t find a Python library for time series generation (not analysis). Something where you can build some models (e.g. loan, income, expenses) which depend on a common parameter (time) and then evaluate all your models for different values of the common parameter. Right now, I generate pandas series/dataframes and combine them afterwards, which also took some massaging of pandas (which I also usually don‘t use a lot).