You could try the contra modified version of Wendy Crouch's Winter Solstice
(square with an extra couple). Renamed Swinging Solstice for the other side
of the Pond. Features a grand square for 5 couples! Progression is
clockwise.
Although they do not feature swings she has Silver Thread ( 3 couples in a
line), which can be prove a challenge even for experienced ECD dancer; and
Sussex Martlets (3 couples in a delta formation).
Graham Knight