All of these things are failures only of bureaucracy to keep up. I should be able to notify the government of who my default estate recipient should be. Maybe it's my best friend or some stranger. No marriage required. Tax treatments for married couples need to disappear and flatten out in general. Insurance should be an individual matter or if it's going to be provided by the government (read: all of us are forced to pay for each other), healthcare issues disappear. The only thing basically left is an adoption issue which is more or less an edge case in all this.