#3
Not to mention it might be too weak to mount hardware. I'd be concerned about bridge/tailpiece studs being pulled out by string tension, especially if there were a trem.
#4
Yeah red cedar is ridiculously soft. Makes pine look like a hard wood. Spanish cedar, on the other hand, is suitable for my Cordoba Spanish acoustic neck.
#5
Cedar makes great firewood.. not to good guitars though haha it's just a little to weak. But seriously though cedar keeps me very warm in the winter, not even joking.