I love Paper but I'm dying for a desktop app, even if it's just a webview in a native wrapper. This would go along way towards helping stay focused given the 50 tabs I usually have open for work. I've tried various hacks for launching a website as an app but none of them work properly.
I also would love offline access to edit & save docs.
Moreso than adding new embeds and content types, I feel these changes could go a long way towards supporting writers and creators who are often working and planning from laptops, whereas mobile is for saving files and quick edits or notes.