Do you find the other greatswords in the game OK?
their damage is the highest in the game, but I find their animation loops to be way too long, coupled with the fact you can trigger a second animation before finishing the first , you get stuck in 4 to 5 second long animation loops while the enemy has moved along, leaving you swinging a sword no where near where the target is......
2 things kill DPS , not having enough damage and not being able to hit with anything, I find they all suffer from one or the other
if the ISO greatswords have a fixed faster swing(haven't built one yet) than the damage needs to be "alittle" lower than the in game one to keep the DPS close, but it sounds like its way off
if the design affects the swing speed the damage model get way more complex as it has to balance out DPS , putting the burden on the player in designing a good sword , but if you can't even get close, than the player will stop trying, which leaves a few questions, Why bother with greatsword ISOs? and If nobody is using them why waste time developing the system?