There was some guesswork involved in the placement of the lobster clips and D-rings, but I like how it came out. I used a two-inch piece of the strap webbing to attach each piece of hardware and then used pattern piece L to make a strip to cover the raw ends of the webbing. Even with careful measurement, one of the lobster clips ended up too close to the edge of the flap, but for a learning process, I'm not fussed over it. I'm quite pleased with the overall result of the bag.
I was going for something that was rugged enough for my tastes, but still could be used in a professional environment. I might not be taking this on job interviews, but otherwise, I think I hit the mark. The only sad part is I haven't been able to use the bag yet because it doesn't quite suit my needs for my work commute, but on my first day off, I'm using it!