I kinda agree with the OP and i have played through all 4 regions on multiple accounts. 1 tip i would give to every single new player is just to solo each region with the starter water pokemon as using a full team comp will limit how fast you are able to progress. Blastoise can literally solo kanto due to be able to learn dig tm and then you can buy ice beam and earthquake tm's for every other region out there, only ever needing to stop and grind for the rayquaza/deoxy fights.
TLDR: Using more then the starter pokemon actually hampers you with how the experience works in this game.
PS i can speed run kanto in 6 hours, i know what im talking about.