I've no idea if it's even possible but an option to allow making a save game during a mission would be a huge help considering some of the bugs in the game can result in having to repeatedly restart a mission
failing that an option to make a checkpoint save (used on mission failed screen) into a proper save (ie: visible on load game options and not automatically overwritten) would be extremely handy
failing that an option to make a checkpoint save (used on mission failed screen) into a proper save (ie: visible on load game options and not automatically overwritten) would be extremely handy