The idea is great, but it gives some very weird ideas, like having 4% interest p.a. (not something I think still happens in the west). Maybe add a stock market

The idea is great, but it gives some very weird ideas, like having 4% interest p.a. (not something I think still happens in the west). Maybe add a stock market fonds aspect in there (which may rise and fall), have more risky, more potentially lucrative, and less risky, more stable fonds in there.