Queuing is pretty handy a feature. Long click then "add to queue" while clicking around in the app while something else is playing. Smart downloading means there's something to watch while offline without having to explicitly pre-downloaded something. If you're a video quality aficionado, there's better picture quality available. An in-app sponsorblock equivalent was being beta tested but I think it went away. YouTube music except that not all the videos are licensed. There's a couple others. But yeah, ad-free viewing is the primary reason I pay for Premium. Supporting creators is another.

The question is how annoying the ads are. One 15 second ad before an hour long video, I'm annoyed but I'm not going to flip the table over. 5 minutes of ads every 30 mins? At some point I'm getting annoyed enough to cancel my subscription.