If I were you I wouldn't right an entire entry in "story" form in your journal because it may wake you up too much to do a fild. I've never done one succesfully because I always seem to "forget" to move my fingers after a while, but I would imagine if it takes you longer than a few minutes to fall asleep you'll probably be unsuccessful.

If the brainwave gen thing helped you increase your dream recall than I'm sure its got some beneficial effects on your lucid dreaming chance. I'm not sure what a brainwave gen is, though, so I wouldn't really know.