Considering this was an uberfort, it was built suprisingly quickly, though the blockcount was quite phenominal so it wouldn't really be viable in a real match, but regardless you might be able to steal a few ideas from it.

Inside of the fort, you can see how all the different wall layers are easy to access for repairs from inside the fort. 3 layers in total. 2 battlements provide optimal coverage. A third was later added between the 2 exit ramps. In the middle is the flagdrop which doubles as a foward bunker.

Side shot showing the enterance. The side defences are layered 4 times. The enterance was rushed because of the remaining time - I still had the flag defence to do at this point.

A better shot of the enterance. Easy to knock people out and even if that 2x1 3d block is removed it's still impossible to jump up on top without a rocket jump.

Front wall showing the flag drop/centeral bunkre and ramp exit points. The shape of the wall maximises space to move around inside the base, but minimises area outside making it harder for the enemy to avoid your fire.

A shot from one of the ramps showing the height of the base and the middle battlement point.

A sniper running up to the flagdrop/bunker. That area is reinforced to 4 layers as the hole suggests a weakpoint to the enemy.