Record of Lodoss War was SOOOOOO based on D&D (Dungeons and Dragons) which made it so excellent to watch way back then.

It wasn't that Japan was ahead, it was that America just stopped trying to make good cartoons.
Japan never watered down their anime for children. (this is why Bugs Bunny is still so funny. It had jokes for all ages)

OnePiece has drinking, fights, death, smoking… which was all erased by Nickolodian when they aired it in the states.

I highly recommend Ranma 1/2.
It is older than Record of Lodoss War, but its art is still pretty top notch, and the story is great.
It seems episodic, but the characters and their relationships are changing over the entire time.