Toss the lettuce, strawberries, blueberries, mango, tomatoes, raisins, almonds, and onions together in a salad bowl. Cover, and refrigerate at least 30 minutes to allow the flavors to mingle. Do not refrigerate more than 4 hours.
Place the bacon in a large, deep skillet, and cook over medium-high heat, turning occasionally, until crisp and evenly browned, about 10 minutes. Drain the bacon slices on a paper towel-lined plate. Crumble and sprinkle over the salad to serve.