Some mockups I did today with potential gameplay... they might not end in future games, but I think it can be useful in some ways to share these ideas... feel free to adapt them for your games
(The normal version is shown next to the "gray" version.)
Jumpy = a vertical runner with a top-down view. (since it's vertical, the buttons A and B won't be used for actions, but for reset and sound only).
You play a bouncing ball who has to switch between 3 vertical paths crowded by different kind of obstacles.
The C button could be use to shoot bullets.
RPG-battle = a messy RPG battle menu with too much infos (portraits, inventory, life bar, action points...) lol
Wormhole = a puzzle-game similar to a Sokoban mixed with Snake: the snake has to push all the rocks in holes; eating apples make the snake longer.