I would like to make a suggestion to add a foreclosure, garnishing and repossession.
For someone who has a large amount of defaulted unpaid debt, the owner of the loan can:
1. Send a notice of default to the borrower with governor seal on it.
2. Send a second notice after 2 weeks to the borrower with the governor seal on it.
3-a If the borrower has plantations, the lender can ask the governor for foreclosure on plantation and the lender owns it upon approval.
3-b If the borrower has a hideout, the lender can ask the governor for foreclosure on one or more buildings. The lender can reduce the level of the foreclosed buildings until the get their money back.
3-c If the borrower has active trade routes, the lender garnishes their income after taxes are paid.
3-d if the borrower has no reliable source of income but has ships, the lender repossesses those ships until all debt is paid from the value of sale of the ships.
4. If none in 3 satisfies the debt, the lender with the governor seal freezes all borrower accounts and can withdraw up to the value that satisfies the debt.
5. Finally, if this still does not satisfy the debt and the player has any buried gold, the lender finds the treasure map in the borrowers belongings and excavate the borrowers treasure for a turns fee of up to 400 turns to recover losses.