Why not have an option in settings...."task with no due date"
In the todoist settings>start page, in addition to "Blank" and "Info Page" there should be an option for "Tasks with no due date."
Actually if you guys were smart enough....you would make that the main workflow...meaning:
1) as a first time user one wants to just create a list of tasks in no particular order
2) then go back and put them in "projects"....you guys are doing everything backward!...........this is precisely why Astrid was so successful.....barrier to entry/learning was very low.......most people want to just throw a list and then worry about what category an item belongs
3) "Tasks with no due date" then can be sorted by Importance of tasks via your flags ....this is the natural human flow of thinking (I asked 14 of my friends about this--with various background of Phd to blue collar workers--and they all agreed)
If you did the above your product will be so much more usable and way more successful. When I showed people your current interface everyone summarily dismissed it, but when I showed it via the "Tasks with no due date," method I described above then everyone "got it" immediately.