I'm not sure it was the weight, but the size, that was the issue. There is no need for such a large ring in this type of application. The upper and lower parts of the curved ring serve no purpose for the bridge, as the bridge is always 180 degrees away from where the webbing goes through the slots (because the webbing is self adjusting there, thus the bridge is always centered). This is why the Anderson just had an oval ring - no matter where you put the panels the forces oppose each other through the ring.
Additionally, more metal means more chance of metal noises with the other D-ring, carabiners, sticks, etc. I have not heard anything from ESS or Eberhart stating why they went with the larger ring. Further, I have not seen anything from ESS or Eberhart stating any advantage of the bent D-ring compared to the smaller fusion D-ring. There have been many on here which have made a wraptor/Anderson style sling using the smaller fusion rings. Treehopper designed its own rubber coated metal plate for this application.