Is it possible to create subcategories in assignment groups? (i.e. A course is divided into 70% Lecture and 30% Lab. Within the 70%, I want to design 4 categories at 25% each. Same with the 30%).

Also - Is it possible to weight a singular assignment within a category? Or do you assign it more "weight" by assigning more points to the assignment?

From what I've researched and tried, I do not believe there is a way to do this.