I really appreciate the new added estimate time feature. But I have a better idea. You should add time track feature by tallying the task from start time and when it complete. This can be counted automatically by counting when click "do it now" or start time. THen you can add a review windows like column or percent style or calendar table.
I assert this feature is critical because tracking time can let you review how long you spent on each tasks and realize what should do next to improve efficiency. Get thing done with long wasted time is not truly efficient.