I would like to have the ability to view the graph on a daily basis, with the ability to advance/return through day-by-day.
Using 12am-12am or 12pm-12pm slots (or custom 12 and 24hr slots), and then left/right or next/previous buttons to advance/return through the days.
We would then still be able to drag-highlight more defined sections to inspect certain events, and/or view the graph using the already existing predetermined or custom time frames.