Standups with more than 6 people will already create a meeting of at least an hour. I mean, standups help is small teams to keep everyone excited (if you all agree on it!), and nobody likes meetings, so if it looks like a meeting and people need a 'token' to speak, then the point of the get-together is already far gone.

Why not join the meetup with afterwork drinks? That way you can really say what blocked you ánd talk about the things that you'd do in a standup...