I just completed a project using hotlinked modules for an apartment building in Archicad. I have had a good experience in setting up and managing the modules. But I also have experience working with Sketchup. Both AC and SU use Groups to help select multiple objects.
Archicad uses external files for modules and those modules can be repeated in a host file.
Archicad uses groups and you can group several groups into groups, but you cannot access nested groups as you can in Sketchup. I wish we could.
Sketchup can turn its groups into components. These components are somewhat like Archicad modules or Autocad blocks. However, in Sketchup components can have nested components and groups that can easily be edited in any instance and any nesting level. If any part of the nested component is modified all instances in the model file are also updated. Components are not like modules as they are not external files. Another nice thing about Components is that they can be animated by scripting and interactivity. In Sketchup I can double click any instance of a component and edit it or keep double clicking deeper into the component to edit. It is really easy to use and manage.
I wish that Archicad had Components to function as they do in Sketchup. The Modules have their place, as do library parts. But Components would fill a gap of easier functionality that is missing. (And while you are at it, update the Morph tool to function like Sketchup modeling. Morphs are too clumsy and difficult to use)
Groups in Archicad are not that helpful and nesting groups is nearly useless since the nesting is not accessible.
My wish is that Groups in AC would be improved and that named components as in Sketchup would also be incorporated. Such components could do much of what modules try to do only better, while allowing to edit the component in the model.
If you know what I am talking about, feel free to add some clarity to this. I speak too briefly here to be helpful to explain this wish.
On hold