Spaces are fine but the general topic tag cloud is not great. It provides no order to help people understand how to navigate a space.
For spaces to be really useful, say as a Knowledge Base, you need some form of navigation / organizing principle.
Perhaps something like this:
- For a given space, create an option in the Space management view to enable space navigation
- From within that option, create the ability to add named navigation groupings
- Allow posts to be tagged directly to navigation groupings and/or using Topics
- Nested navigation would be nice eventually
- Display the navigation element on all the associated Space views