Would like Scope Box Handles to be larger. They can be difficult to grab on a large and complex 3D view. Maybe they could be adjusted as a User Preference with graphical constants Small, Medium Large X-Large.
Larger would be good, but I'd rather see them placed at the corners instead of the center of each edge.
They are often hard to even find - much less select - when they are in the middle of a busy elevation
Have you tried 2018.2? It's a lot easier to select them now.