Are there specific power management settings that could lead to 'documents waiting' issues, especially with USB printers?

Yes, power management settings can cause issues. For USB printers, if the 'USB Selective Suspend' setting is enabled in your power plan (Control Panel > Power Options > Change plan settings > Change advanced power settings > USB settings), your computer might turn off the USB port to save power, disconnecting the printer and causing jobs to get stuck. Disabling this setting can help maintain a stable connection.