=)
As I already stated on the Pokémon Crystal's Reflection thread, the CBS (and the game itself is great), but may not be functional, being hard to use and such (because the game is made on the limited Rm2k3).
So, that said, we must analize what is a "Good CBS"? A CBS that is good looking on screenshots? Or something more, let's say, advanced. For me, a good CBS (or any other system) is that easy-to-use, where you don't have to copy hundreds of IF statements to make it work.
That's why I vote on Pokémon Red, Blue, Yellow, Whatever, etc CBS.
No more,
~Azura.
You can visit the link in my signature to know more about my Pokémon CBS.