I can give you a perfect answer, cause I had about the same build (the 70/70 bow build, which comes down to about 2:1)...
I had a sos+3 bow with phys att +0% and mag att +33%....I couldn't kill a bandit archer in 1 shot...it still had a little bit of life...
My suggestion is if you really want to go farming, buy a sos+4/5 bow with decent mag/phys attack...that way you can kill them in 1 shot...
Or, just start over, which would take only a few hours and make a pure int...then for lvl 17-24 just only add str, so you'll be back at the 2:1 build...