I think, generally speaking, society's morals have improved over the ages (glossing over the whole "what is morality?" debate — but you get the gist of what I'm trying to say). There's a theory known as collective rationality which posits that, as individuals, we are highly irrational beings, but as a holistic group, we eventually arrive at the most rational conclusion to an issue (even if it takes a very long time).

Collective rationality explains why we no longer have slavery, public executions, torture, etc. Women's rights and minority rights aren't quite where they should be yet, but the situation is certainly a lot better than it was a century ago.

I've tried to imagine how society will be different in the far future, and my best guess is that forgiveness will be of tantamount importance to society. The whole notion of "getting revenge" will be considered an ancient and barbaric concept, along with the whole prison system (punishment vs rehabilitation). The death penalty will almost certainly be gone. I think crime will be considered more of a mental illness or a physical brain defect that can be fixed rather than something that makes someone inherently evil (if someone is born with a damaged amygdala, is it really their fault that they turn out to be a sociopath?). I also think a lot of things that are currently considered taboo will no longer be considered as such, barring anything that brings harm to others.