if its goldfarmer then go kill mobs -8 / -9 lvls - they will still give u nice ammount of gold. i belive that max gap to have a drop is like -20 but after -10 drop rate could be just too low. Thats why i reccomend -8 / -9...mobs will be low enough to kill them without diyng and hi enough to have decent drop rate.
Next thing is % of HP to use potion...i always had 35% and i was always using large or x-large pots...if u dont wanna die on giants and pt mobs u should have potion which gives u almost max hp in 1st or 2nd recharge (every pot has 4 recharges)
U dont have to worry about mp since u have Mana Cycle but few vigors on 20% HP would be guarantee of survival on giants and pt-champs.
Life control would be too risky - u would die a lot with it. U are going to hunt -9 lvled mobs so u will have em on one normal attack, dont even mentioning fire or ice nukes :P Life Contorl is useless then.
As for the skills: E.Shock, S.Wind, F.Bolt, I.Bolt for normal hunting.
same + Fire Blow on giants and pt mobs.
Of course u should keep -0 gap on mastery to wear best set...and because of that u should never go to kill mobs bigger than -8 / -9 cuz they would give u too much of exp
and the GF duty is to not lvl up but earn gold and everybody knows that lower lvl mobs have better drop rate (thats why u hardly find a GF over 60-70lvl)
