I prefer option 1. Gargemel is a very developed map, people have a lot invested in it, and i'd like to keep using what i've made here, but still have 1.8 terrain. Those who want to leave their current towns would be able to do so, and found a new one in the newly generated terrain. While those still attached to their current towns could stay. This seems, to me, to be the best option, as you please those who wish to keep gargamel, and those who want 1.8 generated terrain and newness.
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