Format by Outline Level as in Ecco
In Ecco Pro you can apply text format to all items in a given outline level with a single operation.
This is a no brainer. Outlines that only display 1, 1.1, 1.2, 1.3, 2, 2.1, 2.1.1, 2.1.2, 220.127.116.11 is annoying. Pretty much every outliner I have ever used allows preset and custom formatting. There are many thousands of people that use outliners to organize their thoughts, and none were better, and none are better, than Ecco Pro