Do you have ideas for a new world?

[Superelch]

Hello together,
I'm planning to make another world.
My first world is unfortunately broken due to a problem with my computer, but now I'll try making a new one.
I had the idea, I'd let Tux travel around the whole world and even to the moon to rescue his brother Tox who was kidnapped by Nolok.
If you have any tipps, tricks, ideas or suggestions for this world, please share them with me!

[Superelch]

I'm espacially searching for a good background story.
I've got the plan, that one enemy, e.g. snowman, suddenly becomes Tux's friend, but I have no idea how this could fit in a background story...