Be able to apply a new or predefined schedule to any entity and assign value(s) to a schedule segment (eg light level is 10% at night and 100% in the evening, or a programmable room thermostat that has different temperatures for each defined part of the day).
Nested schedules - a child schedule that can override the schedule of its parent - eg, your house heating is no 14 hours a day but some rooms only need to be heated in the evening but should not go on if the parent schedule is off. Greater granularity (15mins rather than 1hr) would be nice as well as a built in ‘randomiser range’ either side of a scheduled time for security lighting.
Easy scheduling (and in particular, easy control of heating, the most energy intensive activity in a home) should be a fundamental core of a smart home.