There should be several ages of consent up until 18. The only person who should get in any trouble is the adult. The ages before 18 should be ages that allow sex within a certain closeness of age. For instance it should be legal for an 18 or even a 19 year old to have sex with a 17 year old. There is no taking advantage of here because they are close in age.
However, no age limits at all is unacceptable. A pervy 30 year old man having sex with a 14 year old is just plain wrong!
There is no possible way to actually enforce with any legal or acceptable means the prevention of sexual intercourse between two willing individuals. To that end it is better to replace the age system that is currently punishing with a misdemeanor for underage sex with a program that encourages the option with education and by granting the needed materials free of charge to those of age normalizing sexual activity and likely reducing or at least enhancing the management of said activity between persons.
Laws regarding ethical positions and differences in development (statutory laws) would be still upheld though in the case of statutory laws the addition of the person to the sex offender registry should be removed unless there is recidivism and it involves more than one individual relationship. The reason being that barring a 17 year old from a 20 year old or a person who just turned 20 is ridiculous and has no sound effect on the moral nature of the problem itself.
The law has no right to enforce penalty on those between individual who willingly to have consensual sex because it's unconstitutional.Age of consent is an discriminatory evil act against innocent people who never have an intention to be violently abusive.It's as worse as to sodomy law where police force incarcerated homosexual having sex in private room.Age of consent with sodomy law should be repealed all together .Such kind of law become archaic and is ineligible in today centuries.
There is no practical way to enforce a law limiting the age at which two willing people are allowed to have sexual intercourse. A better way to deal with this would be to simply DEAL WITH IT, fact is, once a person is sexually mature, they are going to want to have sex (unless they are asexual). There is nothing wrong with it as long as both people give consent.