You know what's a good place for init Files? A standardized place...
A place, where one would expect it...
You know where isn't a good place
/usr/lib/systemd/{user,system}/

You know what is also a fuckin bright idea? Generic names....
Postgresql-10 is a rather anoying service name, if your plattform doesn't feature autocomplete for your plattform. Looking at no one. *Cough* centos *cough*

Well at least manpages for the service would have been nice...