There was a serious flaw in my strap design which coincidentally I had foreseen but hoped wouldn’t happen. Sadly, the only way to fix the problem was to take it apart and try a different approach.
This time, the fabric store had the materials and I was able to get the proper size rings. I got rid of the adjustable aspect and made the strap solid, attaching to the square rings on either side.
I like this strap version best of all and am definitely not changing it again! In fact, I may make more bags with a strap like this!
(notice the derby love? GO DISLOYALISTS!)