I think I'd have a table and chairs on one side, for eating, and a low couch/glider on the other with a couple of single chairs and an end table or two, as a conversational zone. If you throw in a grill, it will feel pretty full. Or you could get some kind of cabinet to serve as a bar when you're having a party...

Outdoor Party Cart with Ice Bin Cooler · More Info

On one side you could have your grill, and so more people can fit outside you could do either a small couch with a table and a couple of small floor cushions with a area rug, or a table and chairs/ table with benches on both sides

a narrow table might work well in the space as above