Still, I'd rather have textual hints about layout than explicit drag-and-drop. Stuff like "boxes a1, a2, a3 should be presented sequentially" or "box b1, b2, b

Still, I'd rather have textual hints about layout than explicit drag-and-drop. Stuff like "boxes a1, a2, a3 should be presented sequentially" or "box b1, b2, b3 are tightly related and should be presented close to each other" and "box c is the root of its tree" and stuff like that.