I never saw a use to the family gold. If you make an investiment, 99% of chance to receive less then you spent. Perhaps a change in the family conception could be good. Giving the ability to move the house not to every hero of the family, but only to one (the lead, patriarch/matriarch), and allowing you to buy things with the gamily gold instead of secondary spend or support (a time ago someone suggested the creation of heirlooms, some items a family turned as their and passed through the characters. this is a good way to think)