Don't forget the annual foreign income exclusion of approx $107,000 per person.
That only applies Foreign Earned Income so for retirees it usually doesn't apply, plus you can only use the FEIE or foreign tax credits (FTCs) (form 1116) so if you have foreign earned income plus dividends, interest etc then FTCs are best. Many countries tax your worldwide income so when filing for FTCs you mark the box "Resourced by Treaty" on form 1116 so that the foreign tax you pay on your US source income can be deducted on your US return.