List of things that should improve before next stable at least.

--- Things that should improve ---
As for colorcoding weekends etc. use the settings where you select which
days are a weekday. Preferably a selectable color too.
Or let the user select which weekdays are holidays in their region
and color them with a user-selected color.

In the Month-view of the calender the Weekends should be colorcoded in
another color (soft red). Days with Fullday but other meetings as well
event's should also have a different color. (soft green?)
Same goes for the Week-view.

These color codings should ofcourse transfer over to the summary page.