Re: "Athletic Training"
The agility ladder is worth some time in your warm-up. Tyler Hass makes a nice one (he also makes the Elite Rings).
As for balancing on swiss balls, it doesn't have any carryover that I know of, nor should it. If you'd like to learn circus tricks like that, save it for your "rest" days. Otherwise forget about those.
Slide boards and Indo Boards are pieces that I like to improve lateral movement strength-endurance, balance, and coordination.