I'm not 100% convinced (even though I think she's great). Thus far, her $100M plus grossers (which are what you need to do to justify a $20M paycheck in this day and age) are:3 Hunger Games movies, where, while she's the main attraction on the poster, the selling point is "Hunger Games," not "Jennifer Lawrence."2 X-Men movies, where she's barely recognizable for most of the film and is billed third. Selling point is "X-Men," not "Jennifer Lawrence."American Hustle and Silver Linings Playbook--Again, surrounded by other names.The only movies Lawrence has toplined on her own are Serena, which tanked, House At The End of the Street which did $30M, and Winter's Bone, which did $6M. I'd want to see her open a non-franchise picture on her own before offering her $20M (same is true of Pratt).
Do we know what the main attraction of the Hunger Games movies are? A lot of movies have been made from popular YA series at this point - how much of the difference between the ones making ~$100M and the Hunger Games movies making ~$400M is due to Lawrence being a genuine star?
True, though the only two YA books with comparable sales success (I believe) are Fault In Our Stars (which is in a traditionally male un-friendly genre and had no action-y hook to show), and Divergent (which suffered from immense backlash towards the final book).