Not sure if "iconic", but I recommend Millennium Actress for an interesting way to weave a story which goes through the evolution of the Japanese film industry.

Not sure if "iconic", but I recommend Millennium Actress for an interesting way to weave a story which goes through the evolution of the Japanese film industry. The screenplay was written by Sadayuki Murai, who put a unique touch on whatever he worked in (he also worked with Satoshi Kon in Perfect Blue). Also not a film, but I found "Mōryō no Hako" (a short series adapted from a 1995 book) worth watching: at the heart it's basically a crime story, but the execution, with some "hallucinated" scenes, and also the characters are interesting.