Years ago when I was younger, I tried to make an FPS in Alice, and didn't manage it. It's not quite as easy to work with as Scratch (with which I cloned Space Invaders and Pong).

I'm also not sure about Alice's love affair with Java. You can make it display the drag-and-drop code blocks in a pseudo-Java style, or make it display actual (uneditable) Java code in a separate pane. But is this actually helpful? Is it really a good idea to try to move from Alice to a "real" language?