That's actually not a bad idea. We already got elves who use archery as a mean to show their worth, and since centaurs are criminally underused, this would be a nice addition to flesh them out. I personally would add obstacle courses, cause I think some centaurs would be of the mindset that even if you're fast, if you can't swerve or jump over obstacles while maintaining some good speed, it's not gonna do you much good.