More interest in AR variants in calibers besides .223/5.56x45mm.
Interest in newer "black rifles" than the AR, like the highly modular SCAR.
Continuing "AR-ization" of the AK platform, as more AK owners discover adjustable-length stocks and the utility of Picatinny rails.
Optics, optics, optics. More and better red dots/holosights. Digital optics. Optics with built-in laser rangefinders.
Weapon lights with both normal-brightness LED area lights (like a wide-area flashlight, so you can navigate without sweeping everything with the muzzle) AND high-lumen spot beams.
"Black rifles" in appropriate hunting calibers slowly displacing Mauser-style hunting rifles in the field, just as military-style Mauser rifles largely replaced older style hunting rifles over the course of the 20th century. This may occur in time to help save sport hunting, if (1) it gets enough gun-owning nonhunters interested in hunting, (2) land-access and lack of mentoring can be remedied, and (3) walnut-and-wood traditionalists don't push the younger generation away.