I am rather surprised at the scarcity of pinball style games in general and it could be because I enjoy Pinball, Pachinko, and just Marble runs in general, but when you have a game format like pinball a lot of options are available.
For pinball you can make the board fit really any theme you want, and really your imagination is the limit on how the board looks an behaves.
Pachinko is the same way but if you don’t know how it works here is the basics, the player starts with 500 metal balls and you launch them 1 at a time on to the board, you can have multiple balls on the board at once, the balls will bounce around off of obstacles and stuff, like in pinball, but you want them to fall into specific holes, usually the middle one, the holes will give the player ‘points’ but the points are given in more balls to be launched into the game, and that is the gameplay loop. Like pinball the boards theme, design, and effects are up to the designer and are practically unlimited. The ball launcher can either match pinballs, where you hold enter to decrease power from max or it can be like an actual pachinko machine and be a wheel that is spun with the mouse, used in the same way that the spin dial phones are used, or it can just be a power meter that is constantly going up and down.
I does surprise me that no one has yet to make a pachinko game where the metal balls are food and you just feed characters, and there was one inflation based pinball game on DA but you can’t even download the SWF file for it and so it died with flash.
I would love to help make these types of games, but I lack the art skill for the assets that would be needed, and I am kinda busy with other games.
Also if people got permission from artists you could make pinball/pachinko boards based on their characters/stories, you need to get permission first though.
Disclaimer this post is more to get others possibly thinking about games like this.