I studied Wwise thoroughly last winter and I noticed that implementing in Wwise was about a half of the actual sound design process.
What I mean is that of course I designed nice sounds and processed those in Reaper as good as I could but afterwards there was so much I could do in Wwise to make them blend in the game. Timing, pitch variation, saturation/distortion, different game modes (low health, bullet time, wet feet, weather system etc.), reverbs & other time based fx, mixing the levels. And you can easily create certain sounds in Wwise, like wind.
I believe the results would've been a lot worse if I had just created the sounds and handed them over to implementation without any control over them. And that's only SFX/foley we're talking about. If you're getting into interactive music then a middleware is a must IMHO.
Wwise is a bit tricky compared to FMOD. You can most likely start a project now and do it with FMOD while learning it at the same time as it's closer to a traditional DAW. But you shouldn't take a Wwise based project if you don't know at least the basics and preferably more.
Have a nice time learning, it's fun :)