Another possibility is to increase the transparency of the meta grid color:
In the preferences dialog, choose 'Others...' for the meta grid color. In the color dialog that pops up choose the color to be for example white and then increase the transparency as desired. If you are on a Mac, reduce 'Opacity' instead. If you are on Windows, reduce the 'Alpha channel'.
For most users, the meta grid lines are most useful if they are just barely visible. The ideal transparency setting depends on your preferred background color and monitor brightness / contrast settings.