well lets see. gs is worhtless or anti-town, depending on the players. if gramps claim granny like you suspect town has a 2/3 lynch d1 so one of them should claim blue or gs that didnt gun. and in that case it would be nice to have a gun, but you dont because gs wasnt stupid enough.
it can become a mislynch setup if gramps hits granny, which makes it very swingy.
make it dawnstart if you want any chance of being able to make this a playable setup. it will probably need other tweaks too