Ion3 is lacking in a few ways, but it fulfills most of the requirements I have in WM.
Those are:
AutoPositioning selected apps to pre-designated places
Tabbed windows
Multiple Desktops
Scripting support
Changeable Hotkeys
Maximization of Space Usage (No wasted desktop space)
Themeable (Okay, so Ion3 doesn't have icons or gradients... I can live with that.. it's hard, tho.
Aside from the Ion3 stuff, i'm using the following themes to make my "desktop" fit my color-scheme:
my old trusty cerebro gkrellm theme
my 23oz of Cyanide GTK2 theme
the Plastik/Plastiq QT engine
and my cyan CoplandOS xmms/bmp skin.
