There are a great number of books that explore this subject. Robert A. Heinlein's https://en.wikipedia.org/wiki/Methuselah%27s_Children is an early treatment. As you say at least one society (I'm sorry I don't remember the book) became increasingly risk-averse and added to an ever-growing list of death penalty crimes to feed the organ banks. Rather than utopia my fear is that would be closer to the truth.
I don't see death penalty happening in a society where a lifetime could be thousands of years. Its just too harsh, with so much to lose. Perhaps sentencing would grow to centuries.
Go read a few Philip K. Dick novels and see if you change your mind. Take current examples of selfish actors with essentially unlimited funds (billionaries, big business, whatever gets your goat) and envision the world after 1,000 years of uninterrupted influence. It's easy to envision a dystopia where caste returns and you're born into a wage slave job at <large retailer of your choice>.
Yes! The ultimate crime, surpassing even Treason. Perhaps death would be too easy for a Murderer. They would have to face perpetual imprisonment, thousands of years of confinement, to sufficiently punish them.
