Why don't you people who make rediculously long weapons make a different playertype that checks when it scrolls through or opens up inventory if the weapon has a certain value, which could be included without much hassle. If the weapon did have that value, the player would play an animation that would make the body twist sideways, possibly the pants as well. That would make the right arm further back and the left arm further forward, and that would make the scaling look a bit more realistic.
I don't know, I have stupid ideas.