Well, to me it's not that I don't use every weapon, but rather most SNS can be upgraded to a better range where most katanas, GS etc uses online parts for later upgrades... making them less effective due to the lost attack power and sharpness which is only available when you can get online parts..
Heck I finished the game(elder leaving the town clip, singing) with only the Gypceros S set and a few Lao shan lung parts(armour, pants) with the portable versions, I amost easily got my Khushal etc armourswhich I cannot make back in dos due to the lack of their appearance. The random quest pops can really drive you crazy.. plus I don't have decent LS to challenge and break wings off the elder dragons.
Well it's been a while since your posted here.. how's your progress? I'm thinking dos has little left to offer to you now that you have deathprize... I had PBA till I cleared the game... making it my only decent sns.