"What I want is quite simple. To be able to configure and manage stuff with the least hassle."
Then you want systemd. As I mentioned before, the sysvinit start scripts are huge, complicated and error prone (the loop in Apache init script). In systemd all you have is a 17 lines file for Nginx: https://projects.archlinux.org...
systemd adds a lot of extras, and does not take anything away. It adds, a) info on whether the service was started, b) automatic restart of crashed services, c) journald, d) limit resource usage per service, e) simple and powerful service configuration files, f) inter service dependencies management (start Thin only if Nginx is started, or start MySQL after Apache) g) a lot of tools that were missing like systemd-ask-password.
And systemd does not take anything away from you. You can still use all your old school tools and your old style logging, and even the old sysvinit scripts.
"but no standard tool will help you when some opaque software is capturing the initialization process."
I don't know what you mean by that.
"Do you know which flags are passed to eg. your nginx setup? A quick look at the rc.d script will enighten you."
Same with systemd service files, see my example above.
"Is there a bug on the script (it happens more often than you seem to think)? Easy to fix."
In a 9000 bytes script file? You gotta be kidding me. The systemd file is just 17 lines long. The systemd developers have automated tests to make sure their software runs, if you don't trust them, why do you trust the kernel devs or the devs of the services you are using?
"but if not, why the f*ck is it taking control over MySQL initialization? "
What do you mean by that? It starts the service and watches the service that it is really started, and it gives you info that it is started or it didn't started or it crashed. For example, on my laptop:
# systemctl status maradns-deadwood.service
maradns-deadwood.service - MaraDNS secure Domain Name Server (DNS) recursive resolver
Loaded: loaded (/usr/lib/systemd/system/maradns-deadwood.service; enabled)
Active: failed (Result: start-limit) since Sun 2015-04-19 23:49:55 CEST; 4 days ago
Docs: man:Deadwood(1)
Process: 1472 ExecStart=/usr/sbin/Deadwood (code=exited, status=1/FAILURE)
Main PID: 1472 (code=exited, status=1/FAILURE)
CGroup: /system.slice/maradns-deadwood.service
Apr 19 23:49:55 localhost.localdomain Deadwood[1472]: There is no directory /mnt/homecrypt/var/cache/deadwood
Apr 19 23:49:55 localhost.localdomain Deadwood[1472]: Fatal: chdir() failed
Apr 19 23:49:55 localhost.localdomain systemd[1]: maradns-deadwood.service: main process exited, code=exited,...LURE
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