I think Sinnoh was the worst offender here, honestly:
- It had a rainy swamp area with overworld rain.
- It had a large, frozen tundra with overworld hail.
- It had a desert with howling winds and overworld sandstorm.
- There were several foggy mountain passes with overworld fog.
- It also had a sunny beachfront, and a city powered entirely by solar panels, with overworld... nothing.
Kalos is almost as bad, it has all of the above apart from the fog, and I think it's getting somewhat annoying now. In the recent ORAS trailer, it's suggested that the Drought sun is a little more than ordinary nice weather (it looks like the sky is on fire, basically), but I really think there should have been a sunny area or two by now. Sun has been seen as a counterpart to Rain ever since Gen. III, but there has been over a dozen rainy routes so far, and zero sunny ones. Why not, once, make a desert with harsh sun instead of a sandstorm?