Fill a large pot 3/4ths of the way with water and salt. Bring to a boil and add the pasta. Cook as directed until cooked to your liking. Strain and set aside, tossing in a bit of olive oil to prevent sticking and to allow to cool.
While the pasta cooks, prep the dressing by combining 1/3 cup olive oil, balsamic vinegar, garlic powder, salt, and pepper. Set aside.
Prepare the pasta salad by combining the pasta, chicken, strawberries, red onion, arugula, dressing, and optional cheese. Toss to combine, carefully stirring in the avocado at the end. Serve lightly chilled.