Shooooot, I’m down for this as long as Goh isn’t taking the reins. I can just see it!
Ash wins the big thing, he goes home to Pallet Town and just takes care of his Pokémon at Oak’s and helps his Mom out. He has some weekly chats with Serena, watching her contests, and he spends his downtime chilling with Tracey. Maybe some big shot trainer from the big city comes in, hearing about THE Ash Ketchum and looks lowly upon what they think is a country bumpkin livin’ in the sticks of Kanto, only to get rightfully clapped.
Ten years have gone by and a kid from Alola named Lei is raring to go on his journey. The son of two professors, Lei is a genius who grew up with five Pokémon as his older siblings, but not just any five Pokémon, five Pokémon that belonged to THE Ash Ketchum. But he’s now a bit tired of being in everyone’s shadows, including Ash’s. To the shock of his parents, Lei forgoes exploring Alola to go the BLANK Region to create a name for himself.
See, I can't get behind that. I feel like the whole "newer generation living in the shadow of the old" plot point has been done to death for years. Beast Wars: Transformers, Boruto: Naruto Next Generation, and Legend of Korra have all "been there, done that" with the whole affair. Gimme something different! And different, I can provide.
This is gonna seem like a strange comparison at first, and maybe it's just because I've got MistareFusion's "Donkey Kong Dissection" video on the brain, but have you ever played the Donkey Kong Country games on the SNES? They introduce a character into the Donkey Kong mythos called Cranky Kong. Cranky's role in the game is that he was meant to be the same Donkey Kong from the original arcade game. Aware that he's a video game character, and has become jaded towards the then-modern state of video games in the years between Donkey Kong 3 and Donkey Kong Country. So whether it's in the game itself or even in the instruction manual, Cranky regularly complains about Donkey Kong Country itself, accusing it of coasting on its graphics and having very little substance and accusing you, the player, of sucking just as bad for buying it.
The main purpose that served was to shut critics up. By having the game itself lampshade by calling out everything about it that critics could before the critics get the chance, those critiques lose all their power. If
, and it's a big "if
", Pokémon does finally decided to retire Ash as the main character, I think that keeping him around and using him in a manner similar to Cranky Kong, would work far better than another "next generation has to prove they can stand alone" storyline.
Make Ash older. Keep him around for a few generations as a Brock-like mentor to show how far he's come since the days of needing Brock to coach him. And make him shockingly stern and jaded. Anything about this replacement protagonist or the new storylines or just how the anime has generally changed itself without him that critics or older fans could complain about, Ash can complain about himself on-screen!
"Oh, you caught every Pokémon that wasn't in your PokéDex between the first three towns. Well, good for you, except now your team totally isn't ready for this first Gym."
"It's not even a tournament, and you're taking your starter off of your team?! Talk about heartless and uncaring."
"Aren't you going to try and actually get to know these Gym Leaders and other Trainers? No? Well, okay then, Scrooge."
And if you want to go the dramatic route and really
want to have a storyline about Goh or Lei or whoever living in Ash's shadow, I guess
you could combine
the two ideas. Have the new main character constantly and consciously try to prove why and how Ash's various criticisms are wrong, or why they're valid but too dismissive or whatever. Further Ash's development by having him grow to see the merits in the new generation's approach. I guarantee that I would be a bigger fan of Goh if he and Ash more frequently asserted their different approaches to training against each other and worked to see the merit in each other.
But maybe all of that is just me. I don't know.