In a large salad bowl, mix together the cucumbers, zucchini, red onion, tomatoes, black olives, basil, and thyme. In a separate bowl, whisk together the red wine vinegar, balsamic vinegar, lemon zest, lemon juice, kosher salt, sugar, and white pepper until thoroughly combined. Pour the olive oil slowly into the dressing mixture, whisking to combine. Pour the dressing over the salad, and serve.
