Simple: Automatic event / task time adjustment
In many applications, when you create a new task, the automatically suggested time is the next round hour (or the next half hour). I would like to be able to define that the time will be chosen according to this and not at a predetermined time (the so-called "due-time" in the settings).
It has an advantage in itself, but especially when it comes to adding quick reminders. In my opinion, many of the reminders we add during the day (and especially quick reminders) are short-term reminders that we want them to jump within an hour (and then if we want, we will postpone them a bit or ignore them for now).