I'd like to add another issue relating to free packs with paid content.
Creating a download key for a free package only grants access to the free content, not the paid content. There seems to be no way of giving people access to paid content through the means of a download key, you can only make a key to give people the content for free that was already freely available on the page itself.
I know this is most likely not on your roadmap at the moment but just in the offchance that this would be an easy fix I would greatly appreciate it, as my whole business model relies on this :)