Brief comments.
IWE => IWT works for me (this also gives us TWIT, which may also work ;-)
Incorporating hierarchical names into topic titles probably isn't a great idea. The whole structure of TWiki is weakly hierarchical at best, so this isn't a forte. Piling prefixes onto everything will give us something like the verylongtediousgermanounword phenomenon. Not Good (speaking as a 50% ethnic German). Context pointers (eg: NixApplications) is probably sufficient.
Use the parent nodes for hierarchical ordering. Primary navigation is via search and cross links.