My design is a frame of 2" tubing. Originally, that tubing was 11 gauge. That idea quickly changed to 16 gauge. I like using 4" for posts too even though that's probably overkill. It just looks cool.
Since I like incorporating wood and metal together in my projects, I decided to use angle iron for mounting some finished cedar with carriage bolts.
I also thought if you were going to make something that looks like a few thousand bucks, why use that cheesy Stanley gate hardware? My hinges are barrel hinges that are a double design so that the gate fully opens, but I had to connect them to keep them from acting independently. The door locks are mortised storm door locks.
They function like someone who knows what they are doing made them. I don't know what went wrong. Ha! I'm happy with them.