First of all, I want to apologize about my avatar. I was messing around and completely forgot that I left it on - until I came back here. Kind of cheesy!
Nicole (and anyone else, really), you can improve balance rather easily and it can be built into your program - that way it doesn't add time to your program. For example, you could use balance disks, boards or a BOSU trainer for all standing exercises or you can stand on one leg while using resistance tubing.
You can also use a stability ball for many exercises, this really challenges your core and requires you to concentrate on maintaining proper balance.
Another thing you can do, and one that I like to do, is perform swings using some type of balance apparatus. There is a picture of Ernie Els using balance disks one or two issues ago in Golf Digest. In the gym, I have my clients use resistance tubing or a cable and weight stack to work on rotational strength. The addition of the disks is great.
Another note, changing your program frequently is a great idea. It keeps your mind and body fresh - you won't get burned out doing the same old thing.
Keep up the great comments and questions.
Brian