Most prisoners don't want to escape, or cause harm, they just want to finish the term and go home and move on. I'd say you could have the honor system (unlocked doors) for 95 percent of prisoners, by letting them know if they escape they'll go to a more secure and less free prison. Then you make prison a place to learn new skills and get treatment for addictions and therapy, and you'll actually see some improvement in society. Also, send less people to prison.

They can be. If you're curious, check out "worlds toughest prisons" on Netflix, an episode that shows a Norwegian rehabilitation-focused prison. You can see how the place is both secure and warm.