Make a configurable option to select what day is the first day of the week. This is different around the world, and the current setup in the date picker isn’t good for pretty much anyone except Americans.
It currently displays Sunday as the first day of the week. In Europe (and many other parts of the world), Monday is the first day of the week.
An option to select this would save me and other non-American users from clicking on the wrong day because of how the date picer calendar is formatted.