Respuesta a "Internal storage on dead phone"There is a high chance that the phone could be gone but the only way to find out is by opening it up. The LCD itself could be gone and maybe the battery. No harm in trying as you have said the phone is already gone.
Respuesta a "Screen assembly swap between two phones"If you wish to use the touch id feature in this model you will need to swap the home button but when doing so use a little heat and should have no problem.
Respuesta a "Bottom of screen bulging out"As you can see near the power button its is bent and thus the top corner is not sitting correctly. When it is not flush it cause the whole screen to not sit in the housing.