Here's my idea for a prison: each cell is the size of a fairly spartan one-bedroom apartment. You go in at the start of your sentence, and you leave at the end. There's a window, maybe a sunlamp, hopefully a treadmill. Food is dropped through a hole in the wall.
I know what you're thinking: "But solitary confinement baaad!" But we do what we can to keep the prisoners' minds occupied. They'll have free access to educational books and videos, hopefully whole educational programs to let them learn marketable skills. We can let then video-chat with loved ones on the outside. Probably even give them video-chat access to a limited number of other prisoners as part of a "peer support" program, although that privilege would be monitored and revoked if anyone starts misusing it. I'm open to other ideas too.
A prison like this would be nice and cheap to run because it would require fewer guards. It would prevent people from coming out of prison with new criminal skills and contacts. And while it may be less pleasant for hardened criminals who like hanging out with their criminal buddies, it would certainly be more pleasant for first-time offenders who don't fit into key prison demographics like the senator or probably you or I. I'd pick the enriched solitary confinement over having to socialise with the general prison population any day, wouldn't you?