Cook the pasta: Bring a large pot of salted water to a boil. Cook pasta until al dente, then drain and rinse briefly under cool water. Drain thoroughly.
Make the dressing: Whisk olive oil, lemon juice, lemon zest, garlic, Dijon mustard, honey, salt, and black pepper until glossy.
Dress the pasta: Add pasta to a large bowl and toss with about two-thirds of the lemon dressing.
Add mix-ins: Fold in cherry tomatoes, Parmesan, toasted walnuts, and optional basil.
Finish and serve: Add arugula and the remaining dressing. Toss gently, taste, adjust seasoning, and serve cool or at room temperature.