Hi Monica,
That sounds right to me. I suppose that we can look into attaching documents to announcements that get forced out to groups, but you’d still need to create a forum post in order to have discussion around that message.
For now, it seems to me that you’ve got this right. The only issue to think about is that using the system above, most of your members will receive two notifications, which could become cumbersome over time.
As we have thought about the issue of group announcements on the Commons, we have tried to find a balance between the needs of group admins and the preferences of members. Our general sense is that if a member elects not to receive forum posts by email, that preference should be respected by the site. But, because we know group admins rely on the announcement feature, we have kept it so that it can be used as you have described.
I hope that this is helpful. Please let me know whether you have further thoughts.
Best,
Matt