It would be cool for the main mechjeb menu to display which MechJeb module is in control. The little square is shaded when the module is open, but maybe make it green or red to indicate if it is in primary (or secondary/auto) control.

The current skin doesn't have something to highlight the button part of the toggle, but I've changed the color of the text to green when the module is in control. We'll probably change this as we move into a custom skin, but for now it looks good.