Apparently there are 40 cut scenes from the middle of the movie where Peter learns about the individual lost boys, Hook tries to groom Jack and Maggie (Jack falling for it because his dad was always too trapped up in his work and Hook became a father figure to Jack while maggie rejects it).
The movie was almost 4 hours and they cut down the middle a lot so maggie has no story and Jack siding with Hook seems weird and you don't see why Peter changes as much.
Only 9 deleted scenes have ever been released, so we all need to demand the Spielberg cut.