It would be nice to be able to remove the first line indent using “Delete” alone, without resorting to the ruler. In Word, the first line after a paragraph break is automatically indented, but if you want the line to be flush with the left margin (for a subtitle, for example), positioning the cursor at the first letter of the indented word and pressing “Delete” would remove the indent, just for that one paragraph. This is very convenient as your hands don’t have to leave the keyboard to fiddle with the ruler, especially when the ruler is hidden to maximize screen real estate. Is this possible to do in Scrivener?
This isn’t currently possible using the backspace or delete key, but you can use the keyboard shortcut Ctrl-Shift-T to move the first-line indent back a half inch to the left. This will affect following paragraphs (which is also true of using the backspace in Word); you can use Ctrl-T to increase the first-line indent a half inch if you want it back in a new paragraph.
Thanks for the keyboard shortcuts, MM. You just saved me from a lot of frustration. 
Hopefully this will be something possible in a future version.