I think the show will be better once they get to book/season 4 and further, where the movies were slimming down and simplifying the plot way too much. But the first few seasons maybe not. The trailers don’t make this out to be a magical entry into this world which imo is a big miss step
You are right,there is not much material in the first few books,but the writers said that they added more stuff not present in the book: they will show some of Hermione's life before Hogwarts,some Weasley family life at home,the same for Draco Malfoy,and also more stuff with Nicholas Flamel.
So we'll see what they invented for the series