Alas, the "Blacks" article is pretty near useless as each state has its own restrictions on felons. The gun ban is a federal law (though also covered by state statutes).
Addressing, PA specifically. PA restores the voting rights automatically at the completion of the sentence. Pennsylvania does bar certain licensing from felons. Trying to be admitted to the bar, for example, is going to be difficult. There's no prohibition on felons holding public office in the commonwealth.
Outside the law there may be some further restriction. Crimes of theft will certainly bar you from holding some of the industry self-regulated positions (banking, financial advising, etc...). Certain countries like Canada will bar felons from being admitted (even for visits) until they have been deemed rehabilitated. Other countries have similar restrictions (Australia for example).