I see some core team on this thread, so just wanted to say THANK YOU! Awesome job! Keep fighting for the users!
I'm totally the wrong person to offer recommendations on mobile, but so far it works very well for me, but then, I use almost no third party apps, and none of them are Play store only. My only complaint is the hardware (outside of their control).
So then what's the point of having a Play Store without Google Play services?
Signal brings its own notifications, so they work perfectly.
The only app which was broken to the point of unusability was Too Good To Go, which demands that you pick locations on a map which relies on Play Services; the manual city entry is broken.
I use Google Maps only in Firefox Focus, but I've heard that builds of Google Maps up to about a year or so ago didn't rely on Play Services, and with Aurora Store you can manually enter a build number to install.
tl;dr: 10/10, fabulous experience.