I vote AAA for the studs -- they are near your face!
I find that I wear pendants more often than strands, but my lifestyle is casual. I prefer pendants in the summer, too, not as hot and sticky.
It seems like a job that would require travel, much like the artisans who do the nucleus implants. I believe they are contracted by the pearl farms. Or, maybe you mean grading for jewelry manufacturers? Everywhere you go, ask, ask, ask.
My Akoya rope isn't graded -- they are baroque pearls. I like baroque Akoyas with their little fish tails and it's not often that I find white. The nacre is very good, so they have nice tones.
I think it depends on why you want a rope and how you plan to wear it?
I have a 48" Akoya rope that I usually wear doubled or tripled up; the pearls are around 7mm.
I suggest freshwater pearls for the rope. I would buy Hanadama pearls for a strand that would be worn closer to the face.
The necklace came out really nice! I like the gradient colors, and your knots look better than mine. They are certainly interesting pearls, different colors, and some look metallic. Wear it in good health, and be proud of your find!
I'd be curious about the process. I've watched Kamoka short films --carefully taking one pearl at a time-- and it seems like it would take a long, long time to harvest any great quantity. How many pearls are taken in one day? I'm guessing harvesters work in teams? How many pearls are rejects...