Preheat oven to 350 degrees F. Lightly grease a 2-quart baking dish.
Cook pasta in a large pot of boiling salted water until al dente. Gently combine ground round, onion, breadcrumbs, garlic, egg, 1 teaspoon salt, and ½ teaspoon pepper in a bowl; shape into 16 meatballs.
Heat oil in a large skillet over medium heat. Add meatballs and cook, turning occasionally, until brown on all sides, 6 to 8 minutes. Stir in wine, gently scraping up brown bits from the bottom of the skillet. Stir in marinara, spinach, parsley, and basil; bring to a simmer. Remove from heat and fold in pasta.
Transfer mixture to prepared pan; top with cheese. Bake until cheese is melted and edges are bubbly, 25 to 30 minutes.
Let stand 10 minutes before serving. Garnish with parsley and basil.
