a good idea?

Volunteers are at the top of the org chart - they form the Board of Trustees. And yes, the general organizing principle of the work of WMF is to fill strategic and operational gaps and facilitate volunteer efforts. Whether staffing numbers are (relatively speaking) large or small does not say anything about whether we're being successful at doing so. I see no reason why it isn't possible to build a 200 people organization that's wonderfully capable of supporting volunteer work without displacing it, or a 20 people organization that's utterly incompetent at doing so. Each WMF initiative, including this very strategy process, needs to be carefully assessed in how it's influenced and been embedded into volunteer efforts; in every case, there are lessons to be learned for next time, and we need to work together to figure out the best ways to support Wikimedia's mission.

That's all true regardless of whether WMF grows or remains static, but growth almost certainly guarantees that we'll fail more (because we'll do more). Not a bad thing, as long as we iterate, remain self-aware, and get smarter.