The following is a sequence used for a long release retrospective. It was the retrospective for the AgileBrazil 2013 conference. The participants: the event organizers and volunteers; a large group (50 people approximately). It took 55 minutes.
Happiness radar -> 3 Ls -> Dot Voting
The following sequence worked well for my last retrospective: distributed team, 14 participants, one hour. Checkin activity: happiness radar...