Here's the thing though, all bosses were copy/paste get too close and get OHK meleed bullet sponges, Gjallarhorn did it's job fine, the problem was poor boss design. Also with the raid weapons, I'm willing to bet that's because they were elemental, no? So easy fix, break down an elemental raid primary = elemental core, can be attached to any primary weapon of your choosing and permanently makes it that element. Can be taken from the weapon for [x] cost, but the core is destroyed upon removal and cannot be reapplied, you have to go out and get another one.