The best way to solve this that I could thnk of is a test level, where you create ideas without any need of eyecandy or logic. You can play around with special affects ect. there, and come back to your level later. By the time you create your *JuSt 4 FuN* level, you'll have enough ideas to last a week without running out of ideas, resisting your boredom!

Also, if that doesn't work out, you could always find a website or other game that uses great creativity, and play around until you get an interesting idea for your pack.

PS: Only make an outline on paper for large projects. If your level doesn't include backtracking, a puzzle, even a good story, don't make an outline.