Just to chip in on the tiling window managers: i3[1] is a really nice one which doesn't need a lot of configuration. Since switching from Window Maker, which I had been using for 10+ years, it has been the only window manager that didn't make me switch back.
(I tried out Xmonad, Awesome, Stumpwm and some other window managers over the years. Awesome was pretty close to awesome.)
i3 has a couple of issues I like to see resolved but all-in-all I'm very happy with it.
Try scrotwm[1] - it's an xmonad workalike, but it's written in C instead of Haskell (not so important to me), and it has a config file instead of ... Haskell (quite a bit more important to me).
Regarding XFCE, I don't think Linus cares about slick if he would have been happy with a Gnome2 fork. As for bugs, I have encountered only one tiny bug.