Bullet is amazing already. If I were to offer a suggestion for further greatness it would be very handy if we could select multiple tasks, notes etc and bulk change aspects of them.
Examples would be selecting 7 tasks I was supposed to do today and bulk migrating them to next weekend rater than having to migrate each task individually. Same logic could be applied for moving multiple items to a new list etc.
When I first used Bullet I found it very intuitive, like everything had already been thought and one if the very few things that surprised me was a multi-select+change feature that allowed me to perform the same action on multiple items at once.