 
To the north of your starting location there's a land bridge, very useful for defence, with pd's, AA turrets, shield generators etc. To the southeast you can be attacked if you don't send forces there and/or build a heavy defence but never forget the anti missile units else your defence line soon will fall. But beyond that point there's a large empty area with a few mass places. If you start on the eastern part it's turned around. The land bridge is to the south and the path to Northwest.