Bring a large pot of salted water to a boil. Add the whole wheat rotini and cook according to package directions until al dente (about 8–10 minutes). Drain and rinse briefly under cold water to stop cooking. Transfer to a large mixing bowl and drizzle with the reserved teaspoon of extra-virgin olive oil to prevent sticking.

While the pasta cooks, halve the cherry tomatoes, slice the cucumber, dice the red bell pepper, thinly slice the red onion, and halve the olives. Place them in a separate large bowl as you go.

In a small jar or bowl, whisk together the ¼ cup extra-virgin olive oil, lemon juice, dried oregano, minced garlic, Dijon mustard, salt, and black pepper until emulsified.

Add the prepared vegetables, olives, chopped parsley, chopped dill, and crumbled feta to the bowl of cooled pasta. Pour the dressing over the top and toss gently until everything is evenly coated.

Cover the salad and refrigerate for at least 15–30 minutes to let the flavors meld. Taste and adjust seasoning with more salt, pepper, or lemon juice as needed. Serve chilled or at room temperature.