Being a somewhat passive benevolent ruler so far, I'm disappointed that the only way to spawn new leaders is through combat. Historically this may be accurate, but perhaps not. Great leaders were also involved in/created/spawned by huge civilian projects. I propose this rules modification: When a civ completes a Great Wonder, there is a small chance that a great leader is also generated. What think you?
Perhaps an increasing GL-change the more great wonders in a row (without inbetween foreign-completed wonders) you manage to complete. Regardless above, I think they should add a adjustable elite -> great leader percentage probability-input in the game-editor.