There are a couple of other ways to help braking. The first is to modify or recut the cam that rotates between the two shoes to give more mechanical advantage, ie less jacking apart per degree rotation of the cam lever. As with other fixes it does increase lever travel though. The other is to dress the brake shoes as described by Roger Moss about a year ago in Yowl if my memory serves me. This when done at the correct edge will cause the shoes to self energise but of course go too far and it will be grabby. Another tip is to ensure the shoes are actually centred in the drum by holding the brake on whilst tightening the backing plate lock nuts otherwise everything else you do is a waste of time.
There is never a substitute for thinking ahead though as any two speeder owner will tell you….