Make Creepers Avoid Lava and Fire (and explode when lit)

Creepers can be unpredictable and come from nowhere, and can even be completely obscured until they drop from above the player. This is especially problematic when surrounded by lava. By the time you try and knock them into the lava, they would have already exploded, and a creeper explosion knocking a player into lava is almost certain death. Also, since the beginning of Minecraft's development, only Flint and Steel has been able to set a Creeper off prematurely. While this makes Creepers less dangerous around fire, it is also nonsensical. Creepers should automatically explode when set on fire, and should actively avoid lava and other sources of heat, such as fire, in order to compensate. This would simultaneously create new ways to avoid Creepers as well as make them more hazardous when forced into such situations.