This is the current view of the outside of the base. Front view.
It's actually 3.0 because we had it made out of dirt when we started, then we turned into cobble and finally improved to the way it is now. We might make even more changes, though.
This is the main entrance now. I'll fix this. First, I'll change the plates to the stone ones, so they can't be triggered by items falling on them.
A view looking into the base's interior.
View from inside, looking at the outside (duh). One issue that came through my mind was that monsters CAN trigger the pressure plates, therefore, they could go inside at anytime. But I took two hours of my... "spare"... time to work on a rather complex redstone system (don't even ask me how I did it, seriously, I have no idea).
It works like a key system: If this lever is pulled, the doors are permanently shut and will not be opened by ANY plates. If it is not pulled down (actually, right), the plates CAN open the door.
As I said, it took me two hours to figure this out. Shortly after that, I was closing the flooring with cobble and guess what happened? Yeah. A creeper. He blew up the ground near me. I lost a pressure plate and a few redstone wires. I had to work for more ten minutes to fix the wiring.
I rage-quit for ten minutes, then I fixed it.