It would be nice to have a configurable default calendar file (within pal.conf) which is displayed every time an event is added, instead of presenting the default calendar directory only, This would speed up the insertion of an event, since often we work with a very limited number of calendar files (maybe one at a time!).
PATCH
A very simple modification that makes it easier to add a new event to the latest updated calendar file. It simply display as default calendar the one used in the last event adding.
A more advanced version of this may be based on history, or may display the "active" calendars (e.g., change among them using arrow keys).
Since I often use one calendar at a time, this improvement speeds up a lot my work. When only one calendar file is loaded, a better solution would be to display its filename as default choice. However I would take some more time to implement it (this proposal took actually no time at all).