The primary benefit that you will realize with NCE is price protection. The NCE annual SKUs provide 12 months of price protection at your current subscription price. Microsoft is also expected to release 36-month NCE subscriptions shortly that will provide additional price protection.
Microsoft will also be including additional features with NCE subscriptions on an ongoing basis, such as including Audio Conferencing with Microsoft 365 and Office 365 mailboxes. This gives you the ability to schedule Microsoft Teams meetings with a phone number for dial-in users. Other features are expected to be forthcoming as well.