PREPARE the DRESSING: Grate 1/2 teaspoon fresh lemon zest; KNEAD and cut lemons into halves to juice, yielding 1/4 cup fresh lemon juice; INTO a glass measuring cup, pour 1/2 cup extra-virgin olive oil; POUR lemon juice to the 3/4 cup mark; ADD 1 tablespoon balsamic vinegar 1/2 tablespoon red wine vinegar, 1 teaspoon sugar, 1/2 teaspoon fresh lemon zest, 1/4 teaspoon kosher salt, and 1/4 teaspoon fresh ground black pepper (and 1 small pressed fresh garlic clove if desired, using garlic press); WHISK mixture well with fork; SET aside.
BRING bring 3 quarts water to a boil in a large pot; ADD 1 1/2 tablespoons kosher salt and spiral pasta, returning to boiling; COOK pasta according to package directions (do not overcook -- pasta should be al dente).
DRAIN pasta well; RETURN pasta to pot and toss with a very small amount of olive oil to prevent sticking; LET stand to cool.
PREP all pasta salad vegetables and fresh herbs to specifications; PLACE prepped vegetables into a large bowl.
ADD the cooled pasta to vegetables in bowl, combining well.
ADD 4-6 ounces cubed or crumbled feta cheese, without tossing.
WHISK the DRESSING mixture again; POUR the DRESSING evenly over pasta salad; GENTLY fold pasta salad over from the bottom a few times to evenly distribute the dressing and combine feta cheese.
CHILL pasta salad at least 2 hours to overnight.
GARNISH pasta salad with parsley sprig, or fresh basil or mint leaves.
SERVE and ENJOY!