We are a slack heavy company. So we have our own announcement channel for all things Marketing that I actually started so that we could share our updates!
We also do quarterly roadmaps and retros where PM + PMMs present their upcoming roadmap and a retro on their activities from the past quarter. All of Product and PMM go - and we invite our key stakeholders across the business, including the leaders from other areas of Marketing.
Starting with those three functional responsibilities - insights, launch/go-to-market, and sales enablement makes a ton of sense for a team of that size. Depending on the current and future product set, I've also seen teams re-org to match customer segment (SMB, enterprise, etc.) or paired with a product manager who is either tasked with overseeing a product and/or stage of a user life cycle (e.g. acquisition, retention).
IMPACT. So often product marketing teams get snowed under by trying to do all the things. They focus on completeness. They want to have every box checked. But they have no idea if any of it is working. Every other team in the business will have endless needs - endless requests - of PMM, but you have to get good at calling out what metric you're focused on and how you think you can ladder into it. Get good at talking to the metrics of the business and get good at thinking about how what you do ladders into the business stategy.
I actually did a Wynter talk on that very topic! You can watch it here: https://www.youtube.com/watch?v=tNyoCOToq-c
It focuses on building a product marketing org in a hypergrowth startup, but a lot of the principles apply to any first PMM hire.
The tl;dr: there is no one playbook. I outline a process you can go through to identify the most important areas for you to focus, how you can think about establishing a baseline, and how to get cross-functional partners and leadership onboard with your strategy.
Well, to quote Rush, "if you choose not to decide, you still have made a choice." I would say the worst thing you can do is not commit to something. Pick one and roll with it - you can always adjust if it doesn't fit the business. Owning a number is the best way to establish leadership and priorities.
The worst are metrics that don't directly lead to revenue. "Site traffic, asset downloads, content creation, the PMM seeks not these things." Find the outputs that align with your key GTM partners in the company, and drive those.