How about a configurable shortcut key which can maximize window with focus? The Configurable shortcut key can be a single key press (such as F7) or multiple key combination (such as Ctrl+J, Shift + K, etc) and the shortcut key to maximize the window is configurable which would mean that you can change it anytime. Have a look at the image below which displays F7 keyboard key configured to Maximize Window. In Order to maximize the Window you are working on, you would only need to press the Shortcut Key one time. Easy, Simple and configurable shortcut key to maximize window for Windows 7, Vista, XP or any other Windows Operating System.
Shortcut Key to Maximize Window