Keep the ratings system and pre-show content warnings, perhaps even increase their visibility in some way the more "objectionable" the content, and let that be that. Violence, nudity, sex, etc. should be the choice of the network and production company, not the government. Watching it should be the consumers choice, not the government saying when and where they can or can not.
Beyond that, if you don't like it, DON'T watch. If you see the little rating in the corner that shows you wont like something that's going to be included, change the channel to a program that more suits your tastes. If you don't want you kid's watching it, monitor their TV time. Show me a TV that is anything short of a dinosaur and it almost certainly has parental controls. Take five minutes and set it to block certain ratings.
Just because they can show it, doesn't mean they have to, and it doesn't mean you have to watch it.