I think something being referred to as "better than AOSP" is all in the eye of the beholder. If you like all the added features, yes, it's better. If you don't want some of those features, it ends up as the swear word for Android owners "bloat." Personally, I like to start with a clean slate and add what I want. That is just my personal preference though. And for many people, they lack the motivation or know-how to add the features of Sense that are missing from AOSP.