An interesting concept here.
I do question the amount of third parties considering it's half of the roster from this alone. While there's no denying this is a solid 30, I would've upped it a bit by adding the following...
Duck Hunt Dog - One of the very first Nintendo characters
Little Mac - I mean....It's Punch-Out and gives more retro rep
Min Min - More of a recent rep towards the Switch's era
Mr. Game & Watch - Classic retro rep
Wario - He, like DK and Yoshi, branched out into his own series. Gotta put one of Mario's rivals in it
Olimar - The lack of Pikmin reps is surprising. And his series is doing well. Add him in it
Give a decent 36 in total.
Why would you put Banjo and Bayonetta in a proper "gaming all-stars" game? And why would you cut Duck Hunt if you're prioritising the most major Nintendo franchises?
Personally, I feel both of them are solid choices for this. It's more than just about gaming all-stars, but how much they impacted the gaming industry as a whole