Would be nice to be able to create a row in a table from the Calendar display of that table. UI could be a plus button shows up in the top corner of any grid cell (either a day in Month view or a 30 min time slot for in Week or Day view) that would pop open the form to create a card. Date and time would of course be appropriately set.
Edge case would be in cases where the column used for the calendar is a Date only type (no time), then in the Week and Day view, the plus button could appear at some other location, for example near the top of the day label.