And for the rest, I spend most of my time either in my browser or the terminal, so there's not really much I expect from a desktop environment than being fast and stable. I don't really care anymore.
This is a really important point.
The average computer user doesn't do a great deal outside their web browser these days. All they really need a desktop environment to do is point them to the web browser then get out of their way.
Instead of treating both screens as an extended single desktop, each screen is on it's own desktop. This allows me to mix and match desktops at will (most common with documentation), or I love swapping the two screens with each other with this line in my xmonad.hs (https://gist.github.com/2657206):
The default behavior when using a dual screen setup is each screen having some of the workspaces.
You could have gone to straight Debian (assuming you were on Ubuntu). Systemd is not the default, but it works very well as sysvinit replacement.