What risks should I model before choosing a strategy for coordinating Social Security and pension income?

Model the risks that could change the household's income needs over time: longevity, health, employment plans, taxes, survivor income, and the amount of liquid savings available. Also compare what happens if Social Security is claimed earlier versus later while the pension and portfolio withdrawals stay in the picture. The goal is to see how each combination affects cash flow and flexibility instead of choosing a claiming date from one benefit estimate alone.