Start with what readers need.
A newsletter earns attention when each issue answers a question employees already have. Begin with a list of those questions from managers, HR and the front line.
Then give each issue one lead story and two or three short items. Everything else belongs on the intranet.
Recurring sections that work.
Keep a few fixed sections so readers know where to look: what changed this month, a person to know, a how-to, and one honest answer from leadership.
Rotate a fifth slot for local news, a thank-you or a question from a reader.
Beyond text.
A short audio edition lets people listen on a commute or a shift. A two-minute video can carry the lead story with a face behind it.
The same script can feed email, audio and video, so you write once and publish three ways.