Just thought I would post a plan of a basic base layout as I think that sometimes words aren't enough to explain some of the guides ideas.
Obviously the gaps would be smaller between buildings and you can shuffle things around to suit your own taste/ideas.
This is my bases building block if you like, and all that is different to this is my second and third power plants fill in some gaps on the corners of the defense "ring", as you can see there is potential to protect 2 more buildings of your choice between the bunkers and the paired towers.
My mine and metal factories along with my oil rigs are ringed around this, well within the defense towers and bunkers ranges.
My wall blocks are just placed around the edges and spread around to stop enemies from deploying too close as are any spare buildings that don't need that much protection.
The pairing of mortar and gun turrets is important but I will add that if you move the gun out slightly, so that the red range ring's far edge meets the mortars edge, that will reduce the chances of having the mortar baited because the turret will take out any baiting units.
Any one else can feel free to add/correct etc.
User I.D. 1528381
AREA52 'cos 51 was already taken...........