Just a few suggestions:
(1) I desperately need the line width setting (or at least fixed broader margins) in fullscreen mode - with sidebars hidden, notes are hardly readable on the 27” iMac.
(2) I miss the sidebar indicators showing the number of notes on the agenda or scheduled for today; app icon badge would be also a nice addition.
(3) …speaking of which, the icon looks fuzzy when the dark dock is enabled. Have you considered alternative version for the dark interface?
I am huge fan of the Agenda approach - with all the features it keeps the simplicity of analog solutions, similar way Findings did. Keep up the good work!