Well this was an entertaining thread
The biggest thing I’d do is introduce Project Mew at the start. Use this to reframe Lugia, Zapdos and Suicune eps into trial missions. Where if you’re successful, you get a chance to be accepted into it. Obviously Goh would fail both the Lugia/Zapdos ones, before finally getting in with Suicune. So now he’s not just catching pokemon for the fun of it, but has more personal stakes in it. I’d also reduce or remove most the instant captures he has, instead focusing on the mons he actually battles and bonds with. They’re just not engaging and he works better when focusing on mons like Drizzile, Golurk, Aerodactyl, Scizor, Floette, etc
Not to mention more conflict with Ash. Nothing dramatic but he morphed into Ash too quickly and it removed some of his individuality. If he’s a co-protagonist he should be more concrete with his differences. He’d slowly building up his battle skills and bonding with pokemon throughout his key captures, whilst changing his deeper flaws via project mew like they did already. So it’s a more long form transformation
