ShowDirector has an “add cue” options which lets me fill space with cues at a given interval. How do I do that in Finale?
An easy approach is to insert a bunch of shells at the starting time of the period you want to fill, drag one of them to the right on the timeline to the ending time, then select all of them and do “Edit > Distribute evenly.” An alternate approach is to add the correct number of shells, select them, and do “Edit > Stagger” to specify the interval, but that still requires you to know the number of shells. Holding shift down to multi-select shells, in combination with ^C and ^V to cut and paste, can make it very easy to lay out sections. After you paste, you can drag the selected items en masse on the timeline to fill out a section.