I was the same with the gun.used only great sword for almost all the game, used 1 or 2 switch axes but mainly gs. After I got to like hr 90 or so I started using other weapons and now I use these main sets
gs - sharp+1, crit draw, focus, earplugs
gs - sharp+1, crit draw, punish draw, earplugs
sa/ls/hammer - sharp+1, earplugs, evasion +2
hammer/ls - sharp+1, hg earplugs
can't really remember my gun setup though, has a lot of pierce shot boosts. Good set though