I think most places have drug courts, first time offender programs, deferment programs, etc. now, so that at least helps some.
We sort of segregate prisoners based on seriousness of the crime by keeping lesser criminals at county jails or lower security prisons, but we don't do it nearly well enough, especially at the state level. Nobody should be in a place like Parchman or Angola that didn't deliberately with premeditation commit violence against another human. It's somewhat amazing that the de facto sentence to so many crimes is anal rape and that citizens in general just sort of shrug and laugh at it.
I wish they they would tier prisons where at least some prisons did not house prisoners that had engaged in any violence against other prisoners. As cheap as video surveilance is, we should be able to record basically everywhere and determine who actually initiated violence in most situations and move them to the next most dangerous prison level. I also wish it was a baseline expectation that for non-violent crimes, people could pay to be housed in something equivalent of a halfway house, where they kept whatever employment they could but are not allowed to socialize or do anything outside of the halfway house except work. People would complain that it allowed richer people to avoid severe punishment for their crime, but it seems like that would be a decent enough tradeoff if it meant saving the state money to treat other prisoners humanely.