I didn't replace anyone besides Giovanni/Blue and Brock, and that was only so that those positions could pay homage to changes we know exist in the Anime, Brock is a Breeder/Doctor in training, Blue=Gary is a researcher, and then Elite 4 and Champion positions I simplified and gave Kanto and Johto some independence of one another.
I listed those same characters in a possibly rotating role. I would like at some point some realization from the writers that the over-lapping characters for Johto and Kanto Elite 4 and Champion was just plain lazy/silly. The other updates is pure house cleaning that pays homage to the Anime.
Interesting ideas. I don't want them to do anything involving animé characters like Forrest, especially since the games and anime take place in different continuities.
Also, if they mean to do this as an homage to previous regions, they shouldn't replace characters like Giovanni or Blue with brand new characters. There's really no need to replace them. As far as Steven, he doesn't represent Kanto well at all.
I don't think it needs to be cleaned up or organized by league necessarily. I mean yes, divide them up by region per day of the week, but for Kanto and Johto, I think it makes sense to replace certain overlapping characters with other significant characters from those regions, like say instead of having Lance in the Johto set, have Eusine, not necessarily as champion, just as a trainer who represents the Johto region.
I wouldn't necessarily be opposed to them introducing a new member to the Johto Elite Four to give Johto a unique set of Elite Four trainers. However, I think that this should be done in consideration with the 20th anniversary of Pokémon paying homage to Pokémons past. Blue and Giovanni, Brock, they were very important parts of Pokémons past. Forrest is part of the animés past but that's where he should remain, because the games and the animé are separate, and after Pokémon Yellow, I think it's good they remain separate.
I also don't think the overlapping roles were lazy or silly. That was back when Pokémon was still relatively new and we didn't have many of the conventions we have today. Gold and Silver were direct sequels and as such, they kept some of the same trainers for the sake of continuity with Red and Blue. It's simply a case of Early installment weirdness, but for those of us that grew up with it, it was a large part of our cherished memories of our childhood, seeing Lance, Koga and Bruno from the games that started it all, still in the sequels and still being strong trainers.