I'm not nearly as fond of my Diamond secret base as I am of my Sapphire/Emerald bases. It definitely has something to do with the fact that I will never ever get rid of all those rocks. Why you ask? I have no friends who play Pokemon games or WiFi. Not to mention my decorations seem to be cooler in the third gen. You have to go up a waterfall to get to my base in Emerald.
As a matter of fact, it's been so long since I've been to my base in Diamond, I've forgotten some of the stuff I put down there. I know there's a TV, a refrigerater, and a kitchen sink but that's about it.