Pallet deck with stone fire pit. Dig up a small mote area around the fire pit, put a tarp down, fill with sand and surround the area with rocks to prevent the sand from spilling over and to hold the tarp down. And easy deck idea in the back.
This is a backyard that is simple, but nicely landscaped with a patio, lawn area, and planting beds. Everything here is in scale and not overcrowded, not too much. Overdoing it in a garden is something that is easy to forget. Try to keep to scale!