Guy's wich module best for marksman falcony?

Crit dmg 12% + dmg boost 6% Or Crit dmg 12% + attack speed 6% Or Crit dmg 12% + armor pentration 18%

Is it possible to make 3 attribute to reach link 20 ? My max was 20 + 20 + 14

After nearly 100 golden attack model only got dmg stack on two pieces so that out of the equation