Research on romantic genre

I watched plenty of romantic film from around the world right from Hollywood hits Notebook(2004) to Korean film Always(2011).  I noted the main elements of all the film. So I can bring the same elements in my film.

1. Girl and boy are opposite nature.   Bad boy -good girl, Rich girl - Poor boy,  High fashion girl - simple boy.

2. They start with a fight and then fall in love.

3.  They are in same place but still not able to meet each other.

4. both have friends.... which only appears on screen for a while.