That's a big undertaking, good luck! I'll definitely be trying it out once it's playable.
Having a nice list of characters you want is cool, but for now I'd say really pick two (or even 1) and try to get them prototyped and make them feel good to play.
Found Row's channel from a similar thread years ago: https://www.youtube.com/channel/UCo6n98yEksXx0kHT4TA8_hQ
This guy does runs of the Pokemon Stadium games blindfolded. And I don't fully know why, but it's just super chill and enjoyable to watch these videos casually.
He's right at 1000 now. Though I don't see any recent uploads, hope he's not done.