Do you believe an offender who has done prison time should not be penalized upon return to society, or do you believe that an offender who has violated society's rules should be precluded from employment, voting, and so on?

I believe that the prison time an offender serves is his penalty. Once it is served, the offender has been punished for his crime and should no longer have to pay for it. Otherwise, one mistake or a relatively minor crime becomes a life sentence of being consigned to poverty and non-participation in a democracy.
As public intellectual Time Wise writes in his book Culture of Cruelty, the United States today has become a cruel society that blames the victim and penalizes the poor. To me, it seems cruel to further punish a person who has already paid a heavy price due to spending time in a miserable prison by then denying him access to a way of life that brings dignity and self sufficiency.
It forces society to have to support the former prisoner if he is not allowed to work. Denying him the franchise tells him he is a person of lesser worth, no matter what he has done to atone for his crimes. Denying him housing aid, food stamps, and other help he might need to get back on his feet sends the message that his society finds him worthless—and this is more than likely to drive him back into crime or into becoming a burden on society.

Incarceration rates in the United States are the highest in the world. American prisons are dysfunctional and brutal when compared to most other advanced nations. One country that does a better job with prisoners is Norway.
In Norway, prisoners can vote. Politicians even visit Norwegian correction facilities during their election campaigns. In America, released inmates—and even those on probation—are often denied suffrage. Giving freed prisoners the right to vote makes them shareholders in American society, and it is the right thing to do.
A prison record should not prevent a freed inmate from obtaining gainful employment. An inability to find work provides a powerful incentive to commit further crimes. In Norway, prisoners have meaningful jobs; inmates who cook are even trusted with sharp kitchen knives. Norwegian prisons focus on rehabilitation, not revenge. Sadly, American prisons are often violent and dangerous places.
In summary, America's denial of rights to freed inmates condemns them to lives of perpetual punishment. Those who did their time need to be readmitted to society and enjoy the privileges and responsibilities that come with citizenship.