If you're looking for newsletter inspiration, then you should definitely check out Sketch's Beyond the Canvas. A good newsletter should have a clean and easily scannable layout, a mixture of curated content that links out to various types of media (Social, Video, Blog), and provides genuine value to its readers. We like how Sketch mixes in content from their community, events, and new resources. We're also big fans of the adorable feedback icons at the very bottom of the email.