I do not know the causes and bases for your charged under felony.
Any how 25 years is fairly long period. Now law may presume that your being a threat is less.
Based upon your cooperation and based upon your behaviour in the prison your case may be viewed sympathetically.
I suggest that you appeal to the civil authorities stating that you have turned a new leaf and you would not revert back to the previous ways.
Ask them to restore your rights and also ask them to ease the sentencing for you.
You can approach through proper channel like the appeal through the Lawyers, Human rights group and also cite your behaviour in the prison to the respective authorities.
Also you can seek the presidential pardon.
These are some of the ways for you.
Mahesh.