Not that I think it will help, but I sent in feedback complaining about the lack of a "my library" on the desktop site. It's in the app! Why wouldn't it be on the desktop?

I appreciate your input. I am in a similar boat. I just created Google accounts for my kids, specifically so they can create their own characters to play in our family DnD game. The adventures themselves are made through a third party and are specifically designed for younger audiences. I found this thread when I discovered they could not have accounts due to their age restrictions.

Currently, my workaround is that I have all of the characters created under my own account, but doesn't allow me to put them all into a shared campaign. It looks as if I can only add one of my characters to a campaign, which is disappointing. I would definitely pay for a "family plan" account that allowed me to create child accounts.