If there is one major critique I have of the Johto overworld aesthetics, its that they should have played up the "used to be a town of Ninjas" angle to Mahogany Town. Like the Watchtowers are nice, but maybe more.

The Ninja hideout was turned into a Rocket Base, but some of the old hideout should have stayed in the design maybe.

My only other major issue is that all the routes surrounding Ecruteak should have been Autumn, not just Bellchime Trail.