Check that the wheel cylinders aren't leaking, they are pretty easy to replace when the stuff is apart. Also, check that the rear axle seals aren't leaking. If the bearings are original, you may want to replace those as well. Lastly, make sure your parking brake is functioning properly, otherwise you may want to do parking brake cables as well. Check out your brake hoses as well to make sure they aren't cracked or overly worn looking.
Remember to do only one side at a time on the brake job, the drums can be a puzzle after you've taken them all apart! You may want a wire brush on a drill to clean up any rusty parts while you are at it. I also took the time to paint my new brake drums so that they didn't rust and look crappy after a few months. Flushing the old brake fluid wouldn't be a bad idea, either.