Whisk together first 9 ingredients; refrigerate, covered.
Heat sugar in small skillet over medium heat until sugar melts and is a light golden brown. Stir in pecans until all are well coated. Spread on greased foil or parchment paper. When cool, chop into bite-size pieces; set aside.
To Serve: Toss baby lettuces with mango and onion; divide among 8 salad plates. Arrange 2 kiwi wedges on each salad, sprinkle with caramelized pecans. Drizzle vinaigrette over salads; serve immediately.