Did you use 1/2 ply for the sides and the back?My interest was to make it as light as I could. Typical canopies were made of 2x2 frames, but to lighten things up I made L-braces made by ripping inexpensive fir strips and then gluing and screwing, making the L.
This provides strength with minimal weight. These were used on the top front and back of the canopy, which was skinned with 1/4 inch plywood. Here it is upside down without the door.
Door was very simply made with 1/4 plywood with framing on the outside to stiffen it up. Here it is with the canopy open:
And here it is with the canopy door closed: