I have 3 simple feature requests that are not hard to implement and would be extremely useful:
1. Being able to access the filter options (context, tags, etc) outside of the list, i.e. in the main menu. At the moment I have to get inside a list, then select a filter, and then go back to the main menu, to be able to see the overall number of tasks in each list. I don't see any inconvenient in adding the ability to being able to slide the bottom bar to the right to access the filters in the main menu.
2. In the "Display Options" section, the in General Settings, I think it is essential to being able to also have an option to toggle to Show Context besides having the already existing ability to "Show List Names". I think it's an information that would be great to be directly visible without having to open the task.
3. Being able to choose the Week start day. In Europe it is common for the first day of the week in a calendar to be Monday. As such, seeing the calendar in Todo as it is, is not very intuitive and leads to some mistakes.