Obsidian is a tool for knowledge management, isn’t it?
I suggest a plug-in which (possibly create a dedicated vault or not) help in tracking expenses, incomes, dues, receivables etc
Alongwithith some minimal graphical interface for easeness.
Such plugin would help in managing personal finance, including recording experiences and notes and not just numbers.
And if more people join their heads to work on such plugin, imagination can go beyond limits…