Systemd - where are the units?

[musv]

Good morning,

I just switched from OpenRC to Systemd. Despite of many doubts about that thing, the first impression is quite ok. But now I'm at the point, that I have to search for almost every installed program a service-unit. Other distributions like Arch have that systemd units included. As I understood the concept of the systemd units, they should be the same on every distribution. So why is that stuff available on other distributions but not on Gentoo? I installed sys-apps/systemd-units from systemd overlay. But there are only a few units available. E.g. nfs is still missing, apache and mysql didn't start correctly.