Trail Mix

Also, I will definitely play this when you finish.

Oh, and we can't forget the original idea, just a sandbox survival. But I imagine that one would be very difficult to program.

Maybe a plot idea or a gamemode or something could be that you have to find the Tiger Viewer, and repair it using materials that you find or craft within your world?
Another could be a holdout kind of thing, you're given 3-5 days to prepare, and then tons of skeletons and zombies rush your house, leaving you to survive as long as possible, patching holes, and preventing them from getting inside.
A tower defense on the moon, like in the first few pages of You Are a Tiger?

Glad you feel inspirednessed. Start moving your photos.