In addition to the ability to add a task, I would like to add an editable subheader such as Morning or Afternoon or a specific period of time. The daily tasks would then be placed in the right time slot. This would allow the list and board functions to work as a daily agenda in rough form where exact times are not as important and fixed slots for tasks until done, which is common in knowledge work. This is fixed scheduling productivity rather than a to do list approach. It would make software like Google Calendar unnecessary for daily work.
It would be a parallel category to subtask and fit the design well. The option to copy or repeat subheadings would be obvious.
Task: edit report
Subheader: 1 to 3 pm
Task: prepare presentation
Subheader: Before going home
Task: Write email to …
I think this would be a popular feature for individual work in particular and drive users to this app as the addition of the Asana board view made my use of Trello obsolete as ASANA has better task management functions. The subheading feature would make my daily plan agenda obsolete in other apps.