Pokemon should've ended with Generation 4. It was the perfect time to do so. It wrapped up the stories and tied them all (mostly) together. We'd reached PokeGods, so there was no point in making any more legends. The designs of the monsters hadn't gone completely off the deep end yet. It would've been perfection.

RIP Pokemon 1999-2010

I do actually really like Gens 5/6/7, but they were not necessary in the grand scheme of things.