I haven't tried any of the food options at Sapphire but we met some folks who really liked StrongWater Tavern. Also its an insanely short walk to Royal Pacific. Jakes would be my recommendation there. Or maybe some sushi at the bar upstairs.
To get from Sapphire to RPR, follow the path that leads from the dock area towards the street - see pic
Then illegally cross street to get to RPR. You will end up near Tchoup Tchoup. It's a short walk to Jakes from there.