Finally, for serving with meatballs (or whenever you want a sauce to stand out), add crushed red pepper flakes - a little goes a long way, so no more than 2 teaspoons unless (like me!) you like "heat" - then play around until you get the taste to your liking. Simmer about 10 minutes.
This recipe takes doing a couple of times to work out your personal preference for spices. I like a lot of garlic and a good amount of heat, so I use more garlic than listed and nearly a tablespoon of peppers - I like my sauce to stand up to my meatballs!
For a "plain" sauce for pasta, I tone down the heat and add oregano or basil. This is a good "basic" sauce that you can play and change to suit the meal.