>>52680771>>52681025It probably could have worked to have less frequent swaps. Keep Ash for Johto, but then have him win and start with somebody totally new for Hoenn. Then if the Hoenn protag is popular, you can keep them for Sinnoh, and then by the time you get to Unova trying to be a soft reboot with the regional dex, you can have someone new there as well.
That would give each character plenty of room, while also avoiding the issues of having any of them stay a child for decades, or having an ever-expanding roster of mons in reserve that they never actually use.
There's also the fact that swapping out characters would have made it more likely to have more of them with different motives or characterization. Not every MC would need to start as a bumbling novice and end as the champion of the 2nd region they visit, after all.