I don't really care about systemd as long as it works and is fast, but Unity is definitely a failure. It's been 5 years now and I'm still not used to it, and find it a terrible UI compared to Gnome 2.
Not better for Tablets, not better for TVs, and for sure not better for desktop.
The only good thing I like is the windows shortcut to launch an application with the keyboard, but that would be easy to do on Gnome 2 also.
Unfortunately, Gnome 3 was not better, and the Gnome project abandoned Gnome 2, so the remaining support on Gnome2 is too small now to make it work with latest software.
That really sucks.