Be aware that the music selection is implemented in the DLL. You can easily edit through XML which pieces are featured in the existing playlists but the selection of playlists and their conditions for playing require compiling the DLL. But once you are doing that, there is nothing to stop you from using other criteria beyond state religion.
1. No, it does not. Mostly civilisations are destroyed by collapse before they lose their last city, but that is a sufficient condition for destroying them.
2. Probably not if you are going for the Unique Historical Victory, which is very tight and challenging for Babylonia due to its comparatively short history (in game turns) and therefore requires both some experience and trial and error. I would recommend a large European civilisation, such as Spain, France or England as your first game, because they have good modifiers, a long game and lots of different ways to grow and accomplish their goals. If you want someone who starts earlier, China is a good choice as well.
1. No, it does not. Mostly civilisations are destroyed by collapse before they lose their last city, but that is a sufficient condition for destroying them.
2. Probably not if you are going for the Unique Historical Victory, which is very tight and challenging for Babylonia due to its comparatively short history (in game turns) and therefore requires both some experience and trial and error. I would recommend a large European civilisation, such as Spain, France or England as your first game, because they have good modifiers, a long game and lots of different ways to grow and accomplish their goals. If you want someone who starts earlier, China is a good choice as well.