We have about 12-14 people in our supper club and while its kind of big, we always have a great time. We do potluck as well around a theme. To avoid the inevitable scheduling problems that arise with a group that size, we have it the same night every month (2nd Thursday of the month). So if you can't make it, you can't make it. If you are busy that month, then you don't host. Seems to work well for all of us.
Also with our potluck, we don't do a really formal course assignment. The host chooses the theme and main dish. Then all the members choose what to make. We always end up with some sort of apps and a dessert, but then no one gets stuck making dessert if they hate to make it. Sometimes we end up with 3 apps and only 1 side, but none of us seem to mind too much.
The instant we become an adult is the moment when the instinct to love is greater than the desire to be loved