PS3 to PS4 is night and day. Hell, it's moon and earth.

Either way, PS4 runs the game at pretty much max, but it during things like S-ranks, i dont think it makes any attempt to scale, and with all the effects on sometimes it lags worse than the PS3 does.

Simple fix though, just turn off full VFX, or just keep party VFX on during S-rank hunts. There's really nothing else that should significantly impact ps4.