Area that was biggest waste?

I don't know if it counts, but Florina Beach comes to mind. To me, it was always just sort of... there. A few barren maps with Lupins, Klangs, and a couple of extremely dated quests. I remember having to pay a couple thousand mesos to an NPC in Lith Harbor to get there before it was sort of annexed with Nautilus Harbor, but I never felt any real incentive to ever go there. It just sort of became a botting playground for a while and faded into obscurity.

Back when Maple was more about adventuring it was kind of cool to be able to go to the beach. It had its uses for quest completing and coconuts needed for a few things.

Besides cubes, Maples biggest misstake was to move away from adventuring.