The movie is great i don't know why people are criticizing it but it feels like they should have made a franchise out of the novel it's a new idea a great fictitious world with the dark tower protecting the universe and super cool gunslingers(i mean Idris Elba great casting by the way) and a big bad villain (Matthew Macconaughey who is also great in this movie). So worth the watch go for it.
yeah i would root for a sequel considering the fact that there are so many books