Channahon IL Warrior Dash

There was a local Warrior Dash took a couple of pics, thoughts or comments welcome.

I'd have shot at ISO 100 and come off f/8. f/8 is giving you too much DOF here, especially in the first one where the red shirts and the red background are both pretty sharp. f/2.8 or f/4 would have reduced the clutter of those metal barriers a lot, and with the runners going tangent to you it's easier to focus on them.

What focusing mode were you using in the second shot?

I was playing around in Mannual mode for the first time, I was using a single point focusing.

OK, but one-shot or AI Servo? I know there are a lot of other 7D focus settings but they're way over my head.

Just asking because 60003 is the sharpest runner there but she'd not in the middle of the frame. I'm actually a bit surprised that at f/8 the runners in back aren't a bit sharper.

The image was cropped, here is the original and 60003 is dead center and I was shooting AI Servo.