In my opinion, the best weapon to go Force is Blader.
Why?
Shields provide a constant increase of def which will make up for some of the def lost by neglecting Ice. Debuffs from the attack skills are very useful too as it can further help with your damage, combined with debuffs from Force...
Force Blader > Force Bower/Force Glavier
but no matter what, in 1v1 pvp, Force > Ice in case of STR characters.
INT chars shld never get Force