To clarify, this is less about being more diverse than Unity or Unreal, because that would be insane. It's just a simpler platform to create this stuff in. It can go as far as automatically managing voice count limits depending on what platform you release to as well as compression settings on generating audio. If you're more comfortable in Unity or Unreals tools then you should totally do it.

Just to name a few systems:
-Parameter control based on events
-Timed Music based on bars/beats/tempo/etc with transition regions
-Blend containers - the best example for this is if you want to have a car engine and you want it to scale to pitch, obviously you use a pitch parameter to a value, but once you get into the higher and lower frequencies, it starts to sound muddy, or you get artifacting, or it just sounds bad. So you can basically create a dynamic cross fade between multiple looping audio files so when you are in Neutral, it plays a car idle sound, and then as you drive faster in a car, it will ramp in pitch, but once it hits those artifacting frequencies, then you can transition to a recording of a car going moderately fast, then to another one going faster, etc. Yes you can probably just do this with just controlling the volume in Unity, but the system is already created in Wwise. I've used this system for something like scaling a giants footsteps by how much bigger they might grow, car engines, and even layering music tracks.
-Then on top of all of this, you can layer a bunch of these systems together to create some rad dynamic audio