Summer Tomato, Onion, and Cucumber Salad -- 3 tablespoons rice vinegar, 1 tablespoon(s) canola oil, 1 teaspoon honey, 1/2 teaspoon(s) salt, 1/2 teaspoon(s) freshly ground pepper, 2 medium cucumbers, 4 medium tomatoes cut into 1/2-inch wedges, 1 Vidalia or other sweet onion halved and very thinly sliced, 2 tablespoons coarsely chopped fresh herbs, such as flat-leaf parsley, chives, and/or tarragon