The Rebirth map allows you to play countless times in the MCBE. After killing the dragon, you will receive not only a special item that will resume the game. It will also be special enchantments and effects! So the reward is worth it to play. The author, who created the Rebirth map, plans to further develop it in MCPE.
For example, after passing the mobs will be amplified in Minecraft for Android. It would be nice to make items in Minecraft BE more rare. But, there is no a single word of this at Minecraft Bedrock.