I've been investigating an improved text-procesing technique: making the text bolder at the font level, not as a 'photoshop' filter.
Doing this is turning out suprisingly difficult since a font's boldness is actually an inherent property. I've been able to get it to work manually by converting the pdf to postscript, extracting the fonts, running them through FontLab Studio to alter the weight, and reembedding them in the pdf. I'm not sure if it's all worth the effort, but the results do turn out pretty good.
Also, I've figured out how to speed things up tremendously. I'll release 2.1 soon with that change and other bugfixes.
P.S. airlik, i'll bet you don't have autoimager. (better error messages will also be in 2.1)