In the comics which mite be diffrent from the Batman cartoons & TV series, the batcave has multiple entrances.
From Bruce Wayne's mansion all entrances to the batcave are hidden, the one that I know about is a grandfather clock that shifts sideways when you twist the hands on the clock face and it reveals some stairs that goes downwards to the batcave.
In the TV series I remember the bust that reveals a panel with 2 poles that Batman & Robin slid down so I'm sure there is many entrances.
There is also a long tunnel that comes out to a mountain face under the Wayne estate, where Batman comes in/out with his batmobile.
If you have only one entrance people may camp there or place Wormholes there etc
Canobis, is your batcave map in 2 parts (from the above screenshots), the actual batcave and Wayne manor, that makes a good contrast. I like the idea of the batcave being like a space map.
I'm not exactly sure how big the actual batcave is, I know there is a main room with a big computer, lots of gadgets, his batmobile, memorobilia from his adventures, a massive coin, a big dinosaur model.
I just looked in my <B>Batman : The Ultimate Guide to the Dark Knight</B> book, there is a 3d map of it, the batcave is quite big with many rooms, wish I had a scanner could send it to you.