The window managers that you use, should really be based on what your using it for. IceWM is extremely resource friendly and yet is still useful. E is well known for being one of the most graphical window managers out there. Work on E has been executing for some time now, and as more time passes, more managers will become more dependable. A great part of Window Managers, are themes.
Themes help control how the window manages look.
Click here for an example of a theme. Say you want your system to look just like a Mac system. Welp, your in luck because there is a theme out there that will convert the look of your window manager to a MacOS emulation. There is a site full of themes for almost every window manager. There is a infinite amount of software available for the X-Windows system.