Wouldn't the strength of the top 4 SP matter more than the strength of your best SP, even for playoff purposes? I'd rather have four #2 types than a #1, a #3, and a bunch of BORPs.
Anyways, Steele is a #1. You don't need to have impressive K/9 to be a #1, ask Greg Maddux. Steele doesn't give up runs and that's all that matters.