Waze's routing just did not satisfy me. It tended to prefer highly complex routes, sometimes just for the sake of avoiding a tiny little stretch of road where it thought there was heavy traffic. Half the time, it was wrong about the more complex route being faster. When it was right, though, the added labor of following that route wasn't really worth it, because it would only save me a negligible amount of time.
Waze claims to learn your favorite routes. It never seemed to learn anything at all about my favorite routes. As far as I could tell, this feature didn't exist.
The ride sharing update not only made it much more frustrating to share the ride -- before you had a great link you could just paste or share anywhere, now it's some sort of Waze-specific notification which goes away and gets lost after you click on it -- but it also made the ride sharing maps nearly non-functional. Whenever my girlfriend or I would use it, it would almost never actually update the other person's position on the map. We tried this several times over the course of more than a month and the failure rate was very high.
In my opinion, if there were bugs causing it to crash before (which I never experienced), they should have just fixed those bugs. The interface "improvement" was a huge step back for me.
Maybe all this is fixed now. I hope so. But it wasn't that long ago that I switched away from it -- about a month or two after the ride sharing update.