What affects charge skill?

[Xaero]

I am making a LLD lvl 20 charger and need to know what affects charge the most. Should I try to get jewels with +damage +%damage +max damage? Or something completely different?

[Karth]

Even at low levels, charge has sufficient ED that +damage jewels (min or max or both; whatever you can get your hands on with the highest average) are far superior to ED% or ED/+damage jewels jewels (if you can afford good two-mod jewels).

Why level 20? That's an odd level for LLDing.