I've been using xfce for a number of years now, the key attraction is the speed I can open and close terminals, and the workspaces. The new stable version of xfce (4.12) has been out since Feb 2015, I've just upgraded and It's impressive. The new features bring no loss in speed or added bloat.

As a sysadmin I always have a number of terminals open, having organised workspaces makes life easier.

http://www.xfce.org/about/tour

Multiple Workspace Wallpapers

When i first used linux I had looked for this feature. It wasn't a major deal that it wasn't supported, but it's pretty neat to see it.

Window Tiling

Although 90% of the time i'm working in terminator (which has splitting functionality), This is a real smart feature to have when tiling monitoring screens / graphs. By dragging a window to certain edged of the screen the window will auto size to fit in a quater of half or full screen.

Intelligent Panel Hiding

The panels now have an option for smart hiding. In this mode the panels hide when a window is maximised or a window is placed ontop. This is a neat space saving feature, the only change I would make would be to have a timeout for the autohide from the mouse out event.

Whiskers Menu

This menu is not part of xfce packages, but is a realy nice addon. I only ever use the menu for, calculator or libreoffice which is not a common task, but it's nice to know there is a clean and tidy menu waiting should i want it.