I have had my phone from launch day (forgot how many days lol - think few weeks now). I have never factory reset after setting up my phone initially. Have around 100 apps installed. I only saw 1 app (Maps) in the deep sleeping app and sleeping app section. I also see 4 apps in the never sleep section (don't recall me putting them there)
I'm realising that I did a factory reset of my phone about 2-weeks ago, so perhaps I'm not seeing any (automatically) sleeping apps because it's not been long enough.
It does sound like you've had the phone for a longer period than me. I'm surprised there's only 1 app that's been automatically put to sleep, and even more surprised that it's in both the sleeping AND deep sleeping category? That's also somewhat worrying that there are apps in the never sleep category if you didn't manually place them there somehow.