For people who upload a lot of avatars, there are often many Unity projects. It's really annoying to have to make a whole new project and import every single package one by one, waiting for each of them to be checked and downloaded, before being able to even start working on the project.
I think this could be circumvented by a couple methods.
First would be letting users select all VCC packages they want to install into the project, then installing all of those (and their requirements if needed) in one go. Even if the wait time is longer for one sitting, it's preferrable to many short wait times.
Second would be letting users create 'presets' of VCC packages they want, so they can create a project then simply press a button or two and have all the packages they want installed into the project.