After all that effort, I decided to lug the (surprisingly heavy) swing to the porch stairs so I could have a sit in it. I was very happy with the result. Very comfy and it felt solid.
The arm rests were simple, but functional. I wasn't 100% thrilled with them, but they work and I haven't come up with a better option. If I ever do though, they're held in place by bolts so they're easily replaceable.