A- for the effort.
You are better than most of people who don't even understand the potential of an underdog class. However, you still need to do more research on the class itself.
Dps sin/shadow is the best class in objective based warzone. For some maps, who will win is simply decided by the skill of sins/shadows.
For high level deathmatches. deception and madness are both viable by far, just play different role. I had played dps shadow in rateds until the competition died on our server. Then I realized the invincibility of commando/slinger/sage line up. So until the day when a team has such ranged combo, dps sins/shadows don't have to worry about surviving. Even in this case, they still can get spot for playing objectives.
A tiny correction for:
http://tinypic.com/view.php?pic=k0fudx&s=6