I well if you treat kerbal deaths as a part of the game to be avoided and minimised as much as possible, then it adds to the game. In my current save game I design my rockets and every new design goes through many launches, lifting cargo and fuel before I'm happy it's safe for use by Kerbals. I save the launch stage with "Sub Assembly" mod and after 5 or so launches they are saved as "KSL" or "Kerbal safe launcher" any deaths are considered serious. Maybe it's a bit anal but I do have another saved test save game that's all carnage and death lol.