Those additional programs can be freely chosen by distros and/or users. So each of them has to stand on their merit. Though of course they do get some built-in credibility by coming from the systemd project. But for the most part, I think systemd software just tends to have competitive offerings with nice interfaces.
I'm annoyed at it replacing resolvconf. At reboot. At date. At logging. At cron. At ntpd. At network configuration scripts.
Some of these I'm sure make life easier for maintainers. Others just feel like change for the sake of change. Breaking workflows because someone wanted to design a better wheel.