If we consider the F35 to be the equivalent of the F15 /Tornado/Typhoon (particularly in cost) - the next big project is the F16 replacement , in terms of cost (hence quantity) and exportability.
Hilarious as it may sound the F-35 is the F-16
cheap replacement, supposedly being less expensive both to buy and maintain. Go figure.
The next generation USAF fighter, the PCA, is the
high end of the high/low mix and is the planned F-22 replacement....