There are a lot of components in EFL. The #interfaces project is an attempt to provide a more coherent API based on these components.
If the objective is to provide more coherency, why are the components "under" the interfaces being excluded? For example, there are eina types which are returned/used in .eo files, and they are still using the eina namespace? It seems to me that, at a minimum, those types should be moved into the efl_ namespace to avoid confusion. There is also the potential to do some cleanups if such a move/rename were to occur.