General

Blast or Power Stance

Hey guys and gals, I need your pro advice what skill to max-- Blast or Stance?

The skills I currently have are:
MAX Advanced Charge
MAX Divine Shield
MAX Heaven's Hammer
10 Blast (level 20 book learned, still looking for level 30 book)
5 Power Stance (learned level 30 skill book from a previous event)
1 Rush

I do train/grind alot and i do random mini bosses as well, but I plan on bossing at some point, and if it is possible for me, solo 'main' bosses like zak (but that would be impossible for an unfunded guy like me), so im not sure which of the two skills I mentioned above that is more important to max?

Thank you for your pro advices guys and gals!