Sunflower House: fun to play in once the sunflowers grow tall! I have seen this done with on large square with side "rooms" and an entrance area. Fun for kids especially if they plant seeds and tend .making their own playhouses.
second ring on the outside of tall sunflowers then a third outer ring of the tall teddy bear sunflowers. If there are any gaps you can interplant with cosmos, amaranth and nasturtiums or (if there are huge gaps) gourds.