Some of the dungeons that we run in instances could be made into open worlds too. Wanderer's Palace, Amdapor Keep, Sunken Temple....no reason dungeons like this, once we run them and once they are done with them, couldn't be converted into an open world dungeon. The maps are basically there, they would just need to open a few extra spots that were covered by debris in the instanced form and they could make them fun venturing spots open world. Put NMs in them, special fates or make them part of certain quest chains for more lore. There is so much potential to double the world size we have now just by doing that.

Plus it would be fun just from an exploration standpoint.

I shudder when I think of how horrible XI wouldda been if Garlaige, Ugg Temple, Bibiki Bay and other such areas were instance only dungeons. But that's essentially what we have now.