So I've been trying this build myself and uh...
One question really:
How do you get your buffs to "500" if you only have a level 5 focus? I'm currently at level 25 with some crappy gear and stuff, but I have like 20 memorized runes of my buffs, yet they're all level 8.2 or some nonesense because I've got this huge penalty on combat skills. Should I be investing then in my focus and say maybe go a little less gungho on my bargaining for instance or some other skill?