Sorry for the delay in getting this up here. Dutch sent me the larger clips almost two weeks ago, but unfortunately life sometimes gets in the way.
Once again, my initial impression of Dutch's gear is, "this is way cool!" I am attaching a picture with the larger hook on 7/64 amsteel (DHa) next to the the original hook on a piece of 1.75 zing-it (DHz).
I spliced the hook into the loop of a whoopie sling for my tests - picture attached (sorry didn't notice the focus was not on the hooks until I got back to the computer). My main concern with using a hook to hold the end of the whoopie in place was that the whoopie loop spread across the width of the MSH would cause a large spreading pressure on the DHa that would cause it to fail.
As you can see from the picture, this is not the case. In the picture, the blue whoopie, with the DHa, is actually laying on top of another grey whoopie that is laying normal. As you can see the whoopies perfectly overlay, showing that there is no width restriction from the hook. In fact, the DHa is not even all the way extended. The loop on the DHa is elongated to allow it some freedom of movement. In my test, the line was passing in about the middle of the elongated hole, so it would easily accommodate a larger spread in the whoopie loop.
This larger hook will certainly work well as a stopper bead to keep the whoopie from getting pulled into itself - goal 2.
The only improvement that I could ask for would be the size/shape of the hook. In the comparison photo, you may or may not be able to see the difference in the sizes of the hooks relative to the lines they are on. The DHz sort of snaps onto the zing-it and holds its position. The hook on the DHa is larger and just loops over the amsteel and the line can freely flow through it.
Shaking the whoopie sling did cause the hooks to slide down the lines and away from the MSH loop it was meant to control. This could reduce its effectiveness.
Overall, I think these hooks will accomplish all of the goals I put out in my wish list at the top.
However, as I stated in the OP, "I think this is what I want." Oh how quickly things change. Now that I have seen the Dutch Buckles, I now think that the whoopie loop will be held in place with the cord on the buckle. This will take care of holding the loop so it can not fall off the MSH (or the straps through the buckle as will now be the case).
I won't know for sure until they arrive later in the week, but it is very likely a case of Dutch understood what I wanted better than I did.