uh, let's be completely honest here. Being an author is not a stable job. You might either get lucky and go mainstream and get rich, or you could become a Van Gogh esque struggling artist. I'm not saying don't try it, but its not a question if you should take the million dollars. With some good investments, you can become insanely rich while living in comfort working on your books and pursuing your publishing contract.
and for that matter, most Halo fanboys I know would not recommend ODST