Higher Norton branches don't really add to the whole 360 suite. There are also even higher tiers with added LifeLock identity theft protection, a completely different product. Norton 360 doesn't have a free version, and its paid editions are Standard and Deluxe. There's also Ultimate, but it adds separate products: Avast Cleanup Premium and Avast SecureLine VPN. Avast Antivirus splits into Free, Premium (single-device), Premium (multi-device).
How many features a service has heavily depends on which edition you're looking at.
