Cook noodles in boiling water for 3 minutes (omit seasoning packet, if included). Drain; rinse under cold water, and set aside.
Combine lettuce and cabbage in a large bowl; toss well. Spread lettuce mixture over a large platter. Place noodles in center of platter on top of lettuce mixture. Arrange sweet potato, red bell pepper, green bell pepper, daikon, and bean sprouts around noodles in individual mounds over lettuce mixture.
Drizzle Spicy Peanut Sauce over salad. Garnish with basil, cilantro, and mint, if desired.