>>30513118Half of Hoenn's routes are sea routes, but half of the sea routes are optional so there's no reason to explore most of them but the shittiest and most barren of the sea routes in the game. Plus they're all the end-game as well
As for the rest, they were clearly experimenting what they could do with GBA hardware. That's why Fire Red and Leaf Green are a massive jump in quality when compared to Ruby and Sapphire. Just look and compare the graphics again sometime, Red's sprite is insanely more detailed than Brendan's
You can really chalk a lot of it to system limitation since Game Freak didn't know what the fuck to do with the GBA. While things look visually impressive compared to Gens I and II, the world design is still the exact same as those games and doesn't branch out too much. Just bigger and visually more interesting, which is enough for some people