DeletedUser495 app suggestions and swipe up to search are two features I use the most
Though I'd be lying if I said the aesthetics weren't a factor. I've tried third party launchers but they don't quite hit the bar when it comes to matching the aesthetics of the stock Pixel, especially now that Google has switched over to M3E for most first party apps
The primary reasons I use GOS are network blocking, call recording, duress PIN, that all with Widevine L1 support
Privacy from Google isn't much of a concern for me personally