Hey Joe,
While editing a linestring, you can open up the 'Properties' command (or press F11) and change these settings while in the second screen, then resume editing.
The reason the menus are separate is because they are two different commands. The 'Create Linestring' command just defines the properties and the 'Edit Linestring' command is used to actually key in the coordinates.

It's a bit tricky to merge these windows into one, since we need a distinct command to edit linestrings (vs other objects such as polylines, circles, rectangles which don't require a separate 'Edit' command).
-Josh