It is an interesting experiment not to use packages at all (except for the root package.)
The question that arises then, is, when and why it makes sense to introduce packages. Presumably, the answer will be different from what you would have answered at the beginning of the project.
I presume that your question arises at all, because packages are like categories and it's sometimes hard to decide for one or the other. Sometimes tags would be more appreciate to communicate that a class is usable in many contexts.
