General

What to cube

Hi,

So right now, I have a perfect 15%'ed unique weapon with 9% atk (only useful line). Most of my other equips are epic with 6% luk (6% damage emblem, 7% damage katara). My question is pretty straightforward:

What should I cube next? Should I use black cubes to try to tier up/get more useful lines on my weapon? cube emblem/katara for %atk or %boss or tier up with black cubes?

Thanks for you input!