Song mode is where it's at. Love it to death. I wrote this all from the MD's song mode, sequencing the internal sounds plus external synths:
http://soundcloud.com/gys/tyrantsDid the efx and mastering using Logic, but the song structure and all sequencing was 100% from the MD.
I came from using Reason for everything. It was nice to see the "piano roll" and get a big picture, but I've found that song mode in the MD makes me work differently and get more creative with what I've got.
Try writing a few patterns, then cutting them up in song mode to create fills; for instance for a 16 step pattern, go 5-8, 1-4, 9-13, 15-16, 15-16. My track above uses a total of like 4 patterns, but cut up creatively using song mode.