I stand by with what I've said before -- people should have life in prison unless they are too dangerous (IE, escaping and going on a killing spree). To you, what would be more punishment -- life in confinement, bored out of your wits, every day for the rest of your life, or the end? But yeah, if they're an escape mastermind then we're definately not going to let them sit and plot out their escape and killing spree.
As for a lethal injection, it doesn't hurt, does it? I mean, I've never gotten one obviously, but it can't hurt more than a flu shot. Five minutes after the injection, the on-site doctor declares you dead after checking for a pulse, and from the limited footage of the injections I've seen, your writs and legs and strapped to a table, you're injected, and you die. I've never seen anyone scream / writhe in agnoy or pain, like electric chairs.
Yes, the guillotine was neat back in it's time period (before injections because usable) because it killed them quickly, but how would you rather die -- head chopped off, or injected? And think about your funeral, especially if you want to have an open casket. Your headless form won't be too attactive.
But I think that any form of killing someone is overkill. They should just sit in prison and rot.
The death penalty is closer to Hammurabi's code than any other law that I can think of at the moment. I consider the time period of Hammurabi to be pretty barbaric.
The president is as close as it gets to a king, but that doesn't mean that democracy needs to be changed because it's too close to monarchy.
There's two things wrong with your analogy. First, I doubt you intended this, but you didn't specify which kind of monarchy you were referring to. The government we have is like a constituional monarchy. Second, who said that monarchy was barbaric? Your analogy implies that. In fact, I'd say that Clan x86 operates under a constutional monarchy, Newby is the Queen (yes, the Queen), and the rules are our constituion.