AFAIK, the Fuzz Face doesn't have a good built-in way to increase the fuzz that the circuit's producing. The only way that I can think of right off the top of my head is to use a pair of transistors with higher than normal gains, which would have the effect of increasing the fuzz. Another way is to add an extra gain stage to the front of the circuit like the guys at Sola Sound did to make the ToneBender Professional MKII. The MKII basically a Fuzz Face with a Germanium transistor gain stage tacked on to the front, which drives the Fuzz Face circuit into sometime next week.
You can increase the output level of the circuit by replacing the 470-ohm resistor with a 1K or 1K2. Also, to prevent Q2 from saturating, you can change the 1KB "Fuzz" pot to a 2KB...which is one of the "Roger Mayer" mods.
Yeah, Phillips' suggestions are about all you can do with a germanium Fuzz Face. If you really want more fuzz, build a silicon FF or a Mayer Axis Fuzz!