The cure is obviously a fan driven smoke unit, there's only so much you get out of a mechanical "puffer". However, in order to get good looking chuffing smoke, you not only need to fit the fan driven smoke unit, but the logic to control it and synchronize it to the chuffs.
Obviously, I use the Super-Chuffer II to control the smoke chuffing. It also offers optional Rule-17 LED headlight control and automatic cab light control. For 4 chuff/rev, I use the Chuff-Generator.
Here's a little A-5 that I recently upgraded with those components.