1. My Google identity is now my real email, the one tied to my real domain that I myself own. That's so much better. I can comfortably sign in/sign up with Google to other sites, have them tied to that email instead of my @gmail.com one.
2. I feel way more comfortable sharing every single detail of my life to Google. In fact, it turns what initially comes off as really creepy, into a useful life service because I'm now using things such as my map activity etc as a service I have a paid contract with Google for. And if I don't like it, I can hard disable the entire service.
3. I have access to a lot of stuff that regular free Google doesn't offer. Things such as undelete email/drive (which has been useful on a couple of accidental occasions), and, get this, support. Live chat and phone!
If only I could pay a monthly fee to include search and maps!
Or, Drive storage by itself, which applies to most products with storage quotas such as Gmail and Photos: https://www.google.com/drive/pricing/
For YouTube, YouTube Red: https://support.google.com/youtube/answer/6305537
Another interesting experiment in the willingness of users to pay to remove ads is Google Contributor: https://contributor.google.com/