Have it take place in a dream; you will have access to all of the genres of fiction for the game and it will also explain the cutesy graphics and whimsical designs.
Pick one or more of the following for the main storyline:
- Quest
- Adventure
- Pursuit
- Rescue
- Escape
- The Riddle
- Rivalry
- Underdog
- Temptation
- Metamorphosis
- Transformation
- Maturation
- Love
- Forbidden Love
- Sacrifice
- Discovery
- Wretched Excess
- Vengeance
- Ascension
- Descension
That list is from the book "20 Master Plots and How to Build Them".
Here is a cliffnotes version of the book posted on a forum.
Toss in a group of mini-arc plots from
here and if you have any problems working with transitions then use the tried-and-true "Oh I just woke up, boy I'm tired, back to sleep!" excuse to skip ahead to the middle of the next adventure.
Pro-tip: always start in the middle of a story and explain "the what and the why" while you're doing it. Good luck Lala, I look forward to playing your game!