introduce 'someday' feature
I've just switched from Nozbe, which is good but expensive.
Although Todoist is very good, there is once single feature I really miss.
You really need to add the feature to star the tasks in one click. Then, I should be able to see all starred + for today - and that will form my today's agenda.
Without that, I have to specifically schedule tasks for an exact date to be able to see them in my agenda. This is too rigid, I always have plenty of tasks I plan for 'someday later this week'. Making me to go and click though the 'due date' field and enter 'today' just to see a task in the todo list for today is too inconvenient.
I even have a task in Todoist: 'find an another todo manager with better agenda support'. Despite I've paid $29 for this year.