Things 3 workflow is based on "timeline’ perspective.
Today is Focus(Priorities) list. It lists following tasks - priority tasks, tasks scheduled for today, due today and calendar events.
Upcoming lists scheduled tasks, tasks assigned future due date and calendar events
Anytime lists tasks having no date assigned (no start date and no due date)
So if we compare everdo & Things 3 workflows,
Today = Focus (+Calendar events)
Upcoming = Scheduled tasks + tasks with future due date (+Calendar events)
Anytime = Next - (tasks with due date)
Please refer to attachments.
What I am trying to convey is that if we can see tasks due for the day & events scheduled for the day in one list, it will be very useful for daily review. Another good example is Microsoft outlook.