THE PICKLED VEGETABLES: In a 4-quart saucepan, heat water, white wine vinegar, sugar, and salt to a boil over medium-high heat. Boil until sugar is completely dissolved, 2 to 3 minutes. Remove from heat, and stir in onion and carrot. Let marinate 20 minutes. Add the cucumbers and radishes, and set aside until the vegetables are softened, about 25 minutes more or longer if you prefer. Drain the vegetables, and pat dry on paper towels.
THE HERB DRESSING: In a blender, puree dill, parsley, olive oil, lemon juice, mustard, honey, and pepper until very smooth, about 45 seconds. Transfer dressing to a small bowl and add yogurt; stir in until combined.
THE SALAD: In a large serving bowl, gently toss together pickled vegetables and salad greens. Crumble feta onto salad, and top with pine nuts. Serve with the Herb Dressing.