Improvements

Create objectives on a monthly basis, and a ritual for planning and reviewing each month.

It happens that I worked on a task previously but forgot to mark it as done. In tomorrow's planning, I do this, but the task remains marked as done as part of the new day! I suggest that if there is any actual time recorded on the task and it gets finished in the future without adding more time to it, it should not be considered a done task of the new day.

Have your tasks roll to the day you get back from vacation

Create a place to manage yearly objectives and be able to connect tasks to them

I'd like a way to proactively see how my weekly workload is laid out, so I can see how much time is scheduled for meetings, tasks, and free time (per day). I'd like to toggle this on/off as part of my calendar or task view so I can see how (un)realistic my week is. Clockwise does a nice job of this (see screenshot) in their weekly review.

The Backlog should be more than a single list of tasks, it should let me organize tasks into projects and columns. Allow the Sunsama Backlog to be a Kanban system itself.

Subtasks should link back to full rich tasks instead of just being text and a checkbox. You should be able to snooze them to future days (just like normal tasks). You should be able to drag specific sub-tasks into the calendar, and ideally this would add time to both the task and sub-task. You should be able to assign them to other teammates.

Allow tasks to be tagged into multiple channels/tags

Due to my work I have calls from 3 different countries, it would be amazing to see their time zones on the left side of the calendar to plan my day or week.