Strength/Hybrid: You should always try to use a Unique weapon cabal alz, if you can make one. If not, at least try to forge Rare weapons in order to benefit from the option stones. For the 1st and 2nd unique weapons, you should be looking for strength, vit, and dex in that order. Starting with the 3rd unique, you should find weapons with +melee attack percentage as high as you can get it.
Why not until the 3rd unique? At a low level you will not benefit as much from the melee attack bonus, as you would the strength bonus since each point of strength is equal to 3 melee attack. Which option stones should you use? HP/MP leech for PvE, damage drop/attack speed/critical percentage for PvP.
Dex: All weapons should be made with +dex or a mix of +dex and +vit and should be using 4 crit option items when forging the unique. Playing a dex build with anything but a unique critical percentage dagger is just flat out painful and we do not suggest it.