My problem is having too many groups. Example: Each of the keyboard keys in the block Q-F has 8 alternative functions. I needed 8 different Group folders, and then a Group to activate one, deactivate all others (x8). See the nested folders discussion here: Feature Request: Folders Within Folders (Or, Groups Within Groups)
For my configuration, however, there's a much more efficient solution: using variables. https://wiki.keyboardmaestro.com/manual/Variables
I can then switch groups and change my numeric parameters over large group of macros without having to make more folders. This helps reduce the number of groups and make the code more modular.