Apart from it would be many more places to walk around and find experience. To start I would suggest a fresh set of mountains with a town on the top covered with snow ( I think it would be cool as there arent any of those). To present this new town jagex could make a pursuit where adventurers heading into the mountains suddenly disapared and that probably it was a monster.
Therefore you would go to such mountains and find a town with some king who believed adventurers were spies trying to steal his gold or something (since the town would be prosperous with gold mines).
Also, so as to enlarge the map we could add another brand new kingdom besides the one mentioned previously. This new realm could be found after the mountain pass (which would be quite harmful by the way) or in a huge island such as karamja. But you are most likely thinking" what is going to be the story behind this place?" .
So... in order to get that you would also have to begin a quest. In the first spot captain Ned at draynor will inform you there are tales of sailors finding a island that isnt from the maps but are frightened of moving there. Your duty is to go research! When you get on the island you figure out people are diferent (cause they're japanese or chinese runescapians). This way we could also add samurai and ninja armour into the match as reward from the quest. I hope that you guys like my ideas about this and also please don't hesitate to provide your opinion! Or, in case you have a diferent and better idea please let me know.
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