In general I agree, but the existence of the death penalty at all is not rehab or restitution, but to cause suffering. I don’t believe in eye for an eye, but if the goal is punishment, death is only an escape from punishment, whereas keeping them alive and in jail for as long as possible is to me way more of a punishment.

Good, death is an escape from punishment. If you want someone to suffer for their crimes, keep them alive and miserable in jail. The only hell is the one we live in now.