3. I was always for "project-less" development because project files tend to be hard to maintain and setup. But in InType it is actually nice. All projects get organized "under one roof". Ability to just access any project via "All Projects" tab in Sidebar is awesome. Downside: there seems to be no way to delete the project so it would no longer show up in "All Projects" tab in Sidebar. I hope this coming in next version.
My only suggestion is - keep it simple; many other text editors try to put too many features and over time version 3.x of the editor is almost like bulky IDE (slow and with 80% of features you do not need).