As far as I can tell, I can either have a Hangouts meeting, or a Hangouts broadcast, where there is one presenter and everyone else are observers. I guess I just want to confirm I'm not missing anything: is it possible to have a video call with multiple participants + observers? Any non-hangouts way to achieve this?
It is possible to have a video call with multiple participants and observers using Hangouts on Air.
Hangouts on Air allows up to 10 participants and an unlimited number of observers. It also includes moderation tools such as a Q&A app.
How do I invite my friends [who will be participants] before I broadcast?
You'll be prompted to invite your friends or circles before you enter the Hangout On Air. Please note that you can't invite the public to join a Hangout on Air, but you can open the broadcast for public viewing. To make it available to the public, click Start broadcast from within the Hangout On Air window.
Source: Google Hangouts on Air Common Questions
Hangouts videocall: it doesn't include moderation tools. Only allow participants.
Hangouts on Air: it include moderation tools. Allow participants and viewers.